Magnetic field regenerator

Description

TECHNICAL FIELD

This disclosure relates generally to a magnetic field regenerator for use in a particle accelerator.

BACKGROUND

Particle therapy systems use an accelerator to generate a particle beam for treating afflictions, such as tumors. In operation, particles are accelerated in orbits inside a cavity in the presence of a magnetic field, and removed from the cavity through an extraction channel. A magnetic field regenerator generates a magnetic field bump near the outside of the cavity to distort the pitch and angle of some orbits so that they precess towards, and eventually into, the extraction channel. A magnetic field regenerator is typically a ferromagnetic arrangement that provides an enhancement to an existing magnetic field.

Heretofore, particle accelerators operated using a relatively low magnetic field, e.g., on the order of 2 Tesla. In such cases, the magnetic field bump produced by the magnetic field regenerator could “suck” a significant amount of the magnetic flux from the interior magnetic fields. This creates a magnetic field hole in the cavity relative to the background 2 Tesla magnetic field. This hole was typically filled by incorporating progressively smaller radially-adjacent magnetic field regenerators into the cavity to add progressively smaller magnetic field bumps in place of corresponding holes generated each by an immediately preceding magnetic field regenerator. Implementing the foregoing magnetic field correction using progressively smaller magnetic field regenerators can be difficult in systems that operate at relatively low magnetic fields.

SUMMARY

An example particle accelerator includes the following: a voltage source to provide a radio frequency (RF) voltage to a cavity to accelerate particles from a plasma column, where the cavity has a magnetic field causing particles accelerated from the plasma column to move orbitally within the cavity; an extraction channel to receive the particles accelerated from the plasma column and to output the received particles from the cavity; and a regenerator to provide a magnetic field bump within the cavity to thereby change successive orbits of the particles accelerated from the plasma column so that, eventually, particles output to the extraction channel. The magnetic field is at least 4 Tesla or 6 Tesla and the magnetic field bump is at most 2 Tesla. The example particle accelerator may include one or more of the following features, either alone or in combination.

The regenerator may include a ferromagnetic arrangement located at a radial location from the plasma column. The regenerator may include a single ferromagnetic arrangement or multiple ferromagnetic arrangements (e.g., there may be multiple ferromagnetic structures of the type described herein configured and arranged to produce the magnetic field bump and/or to shape the magnetic field bump). The ferromagnetic structure may include steel. The magnetic field may be at least 4 Tesla or 8 Tesla and the magnetic field bump may be at most 2 Tesla.

The regenerator may have an irregular cross-sectional shape that is designed to produce a magnetic field bump having a specific shape and/or magnitude. The cross-sectional irregular shape may have an angular feature on a portion of the regenerator facing towards the cavity, where the angular feature includes an edge comprising a non-orthogonal intersection of two faces.

The extraction channel may include a septum that separates particles entering the extraction channel from particles remaining in the cavity. The regenerator may be configured so that a pitch and an angle of a particle orbit enable a majority of particles in the particle orbit to pass over the septum and into the extraction channel. The particle orbit passing over the septum may include a range of radii of particles relative to the plasma column.

An example proton therapy system includes the foregoing particle accelerator; and a gantry on which the synchrocyclotron is mounted. The gantry is rotatable relative to a patient position. Protons are output essentially directly from the synchrocyclotron to the patient position. The particle accelerator may be a synchrocyclotron.

An example particle accelerator includes the following: a particle source to provide pulses of ionized plasma to a cavity containing a magnetic field; a voltage source to provide a radio frequency (RF) voltage to the cavity to accelerate particles from the plasma column outwardly, where the particles accelerated from the plasma column travel in orbits within the cavity; an extraction channel to receive orbits of particles from the cavity for output from the particle accelerator and a regenerator to provide a magnetic field bump within the cavity to shape the orbits of the particles in order to direct the orbits of particles to the extraction channel. The example particle accelerator may include one or more of the following features, either alone or in combination.

The magnetic field may be at least 4 Tesla or 8 Tesla. The magnetic field bump may be at most 2 Tesla. The regenerator may be movable in one or more dimensions relative to the plasma column. The regenerator may have an irregular cross-sectional shape that is designed to produce a magnetic field bump have a specific shape and/or magnitude. The cross-sectional irregular shape may include an angular feature on a portion of the regenerator facing towards the cavity, the angular feature may include an edge comprising a non-orthogonal intersection of two faces. The example particle accelerator may include multiple regenerators of the type described herein configured and arranged in the orbital cavity to produce one or more magnetic field bumps and/or to shape the magnetic field bump(s).

An example proton therapy system may include the foregoing particle accelerator; and a gantry on which the particle accelerator is mounted. The gantry is rotatable relative to a patient position. Protons are output essentially directly from the particle accelerator to the patient position. The particle accelerator may be a synch rocyclotron.

In an example, a particle accelerator includes: a voltage source to provide a radio frequency (RF) voltage to a cavity to accelerate particles from a plasma column, where the cavity has a magnetic field causing particles accelerated from the plasma column to move orbitally within the cavity; an extraction channel to receive the particles accelerated from the plasma column and to output the received particles from the cavity; and a regenerator to provide a magnetic field bump within the cavity to thereby change successive orbits of the particles accelerated from the plasma column so that, eventually, particles output to the extraction channel. The particle accelerator is configured to vary an energy of the particles that move orbitally within the cavity. The particle accelerator may include one or more of the following features, either alone or in combination.

The regenerator may be movable in one or more dimensions within the cavity, such that movement of the regenerator is correlated to an energy of the particles. The particle accelerator may include coils to pass current to generate the magnetic field, where a variation in the amount of current through the coils corresponds to a variation in an energy of the particles. The particle accelerator may include an energy degrader to affect an energy of a particle beam output from the particle accelerator.

Two or more of the features described in this disclosure, including those described in this summary section, may be combined to form implementations not specifically described herein.

Control of the various systems described herein, or portions thereof, may be implemented via a computer program product that includes instructions that are stored on one or more non-transitory machine-readable storage media, and that are executable on one or more processing devices. The systems described herein, or portions thereof, may be implemented as an apparatus, method, or electronic system that may include one or more processing devices and memory to store executable instructions to implement control of the stated functions.

The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an example particle therapy system.

FIG. 2 is an exploded perspective view of example components of a synchrocyclotron.

FIGS. 3, 4, and 5 are cross-sectional views of an example synch rocyclotron.

FIG. 6 is a perspective view of an example synchrocyclotron.

FIG. 7 is a cross-sectional view of a portion of an example reverse bobbin and windings.

FIG. 8 is a cross sectional view of an example cable-in-channel composite conductor.

FIG. 9 is a cross-sectional view of an example ion source.

FIG. 10 is a perspective view of an example dee plate and an example dummy dee.

FIG. 11 is a perspective view of an example vault.

FIG. 12 is a perspective view of an example treatment room with a vault.

FIG. 13 shows a patient positioned next to a particle accelerator.

FIG. 14 shows a patient positioned within an example inner gantry in a treatment room.

FIG. 15 is a top view of an example acceleration cavity and an example extraction channel.

FIG. 16 is a graph showing magnetic field strength versus radial distance from a plasma column, along with a cross-section of an example part of a cryostat of a superconducting magnet.

FIG. 17 is a top view of an example acceleration cavity and extraction channel, which depicts orbits moving to enter the extraction channel.

FIG. 18 is a top view of an example acceleration cavity and regenerator, which depicts magnetic field lines in the cavity.

FIG. 19 is a graph showing magnetic field strength versus radial distance from a plasma column for a particle accelerator having a background magnetic field of about 2 Tesla.

FIG. 20 is a top view of an example acceleration cavity having multiple axially-aligned regenerators.

FIG. 21 is a cut-away side view of an example regenerator.

FIG. 22 is a front view of part of an extraction channel.

FIG. 23 is a conceptual view of an example particle therapy system that may use a variable-energy particle accelerator.

FIG. 24 is an example graph showing energy and current for variations in magnetic field and distance in a particle accelerator.

FIG. 25 is a side view of an example structure for sweeping voltage on a dee plate over a frequency range for each energy level of a particle beam, and for varying the frequency range when the particle beam energy is varied.

FIG. 26 is a perspective, exploded view of an example magnet system that may be used in a variable-energy particle accelerator.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION
Overview

Described herein is an example of a particle accelerator for use in an example system, such as a proton or ion therapy system. The system includes a particle accelerator—in this example, a synchrocyclotron—mounted on a gantry. The gantry enables the accelerator to be rotated around a patient position, as explained in more detail below. In some implementations, the gantry is steel and has two legs mounted for rotation on two respective bearings that lie on opposite sides of a patient. The particle accelerator is supported by a steel truss that is long enough to span a treatment area in which the patient lies and that is attached stably at both ends to the rotating legs of the gantry. As a result of rotation of the gantry around the patient, the particle accelerator also rotates.

In an example implementation, the particle accelerator (e.g., the synchrocyclotron) includes a cryostat that holds a superconducting coil for conducting a current that generates a magnetic field (B). In this example, the cryostat uses liquid helium (He) to maintain the coil at superconducting temperatures, e.g., 4° Kelvin (K). Magnetic yokes are adjacent (e.g., around) the cryostat, and define a cavity in which particles are accelerated. The cryostat is attached to the magnetic yokes through straps or the like. While this attachment, and the attachment of the superconducting coil inside the cryostat, restricts movement of the superconducting coil, coil movement is not entirely prevented.

In this example implementation, the particle accelerator includes a particle source (e.g., a Penning Ion Gauge—PIG source) to provide a plasma column to the cavity. Hydrogen gas is ionized to produce the plasma column. A voltage source provides a radio frequency (RF) voltage to the cavity to accelerate particles from the plasma column. As noted, in this example, the particle accelerator is a synchrocyclotron. Accordingly, the RF voltage is swept across a range of frequencies to account for relativistic effects on the particles (e.g., increasing particle mass) when extracting particles from the column. The magnetic field produced by the coil causes particles accelerated from the plasma column to accelerate orbitally within the cavity. A magnetic field regenerator (“regenerator”) is positioned near the outside of the cavity (e.g., at an interior edge thereof) to adjust the existing magnetic field inside the cavity to thereby change locations (e.g., the pitch and angle) of successive orbits of the particles accelerated from the plasma column so that, eventually, the particles output to an extraction channel that passes through the yokes. The regenerator may increase the magnetic field at a point in the cavity (e.g., it may produce a magnetic field “bump” at an area of the cavity), thereby causing each successive orbit of particles at that point to precess outwardly toward the entry point of the extraction channel until it reaches the extraction channel. The extraction channel receives particles accelerated from the plasma column and outputs the received particles from the cavity.

In some implementations, the regenerator is a single ferromagnetic arrangement that is configured to generate a magnetic field bump having a specific size and shape. In this context, a single ferromagnetic arrangement may be a single contiguous or physically connected structure or it can be two vertically-aligned, but physically unconnected ferromagnetic structures (e.g., one on each yoke) separated by empty space through which magnetic flux passes. In this context, vertical alignment includes alignment between yokes and includes any appropriately aligned whole or part of the ferromagnetic structures.

The regenerator may be made of steel (which includes iron), in which case the magnetic field bump produced by the regenerator is, at most, about 2 Tesla. Other materials, however, may be used to produce magnetic field bumps that are more than, or less than, 2 Tesla. For example, in some implementations, the magnetic field bump is in the range of 0.5 Tesla to 1 Tesla. The magnetic field already in the cavity (referred to as the “background magnetic field”) is at least 4 Tesla, 5 Tesla, or 6 Tesla, and sometimes more (e.g., 8 Tesla, 8.5 Tesla, 9 Tesla, 9.5 Tesla, 10 Tesla, 10.5 Tesla, or more). Consequently, the hole in the magnetic field bump produced by a regenerator that provides a 2 Tesla or less magnetic field bump is small compared to the background magnetic field. As a result, the overall impact of the hole on the particle orbits is less than is the case in particle accelerators that use smaller background magnetic fields (e.g., 2 Tesla). In other words, because the background magnetic field is so high in proportion to the magnetic field bump, the effects of the resulting hole in the magnetic field are less than in lower-field accelerators. As a result, in some implementations, a single ferromagnetic arrangement may be used as the magnetic field regenerator, thereby eliminating the need for additional, progressively smaller, radially-adjacent regenerators to add progressively smaller magnetic field bumps to fill-in other magnetic field holes.

Furthermore, the physical position of the regenerator within the cavity may be adjustable to compensate for movement of the superconducting coil. For example, computer-controlled actuators may be used to adjust the position of the regenerator in one or more dimensions within the cavity based, e.g., on a rotational position of the particle accelerator. By so adjusting the position of the regenerator, it may be possible to position the regenerator so that the appropriate adjustment to the magnetic field resulting from the regenerator impacts the proper particle orbits regardless of the rotational position of the particle accelerator.

The magnetic field regenerator described herein may be used in a single particle accelerator, and any two or more of the features thereof described herein may be combined in a single particle accelerator. The particle accelerator may be used in any type of medical or non-medical application. An example of a particle therapy system in which the magnetic field regenerator described herein may be used is provided below.

Example Particle Therapy System

Referring to FIG. 1, a charged particle radiation therapy system 500 includes a beam-producing particle accelerator 502 having a weight and size small enough to permit it to be mounted on a rotating gantry 504 with its output directed straight (that is, essentially directly) from the accelerator housing toward a patient 506.

In some implementations, the steel gantry has two legs 508, 510 mounted for rotation on two respective bearings 512, 514 that lie on opposite sides of the patient. The accelerator is supported by a steel truss 516 that is long enough to span a treatment area 518 in which the patient lies (e.g., twice as long as a tall person, to permit the person to be rotated fully within the space with any desired target area of the patient remaining in the line of the beam) and is attached stably at both ends to the rotating legs of the gantry.

In some examples, the rotation of the gantry is limited to a range 520 of less than 360 degrees, e.g., about 180 degrees, to permit a floor 522 to extend from a wall of the vault 524 that houses the therapy system into the patient treatment area. The limited rotation range of the gantry also reduces the required thickness of some of the walls, which provide radiation shielding of people outside the treatment area. A range of 180 degrees of gantry rotation is enough to cover all treatment approach angles, but providing a larger range of travel can be useful. For example the range of rotation may be between 180 and 330 degrees and still provide clearance for the therapy floor space.

The horizontal rotational axis 532 of the gantry is located nominally one meter above the floor where the patient and therapist interact with the therapy system. This floor is positioned about 3 meters above the bottom floor of the therapy system shielded vault. The accelerator can swing under the raised floor for delivery of treatment beams from below the rotational axis. The patient couch moves and rotates in a substantially horizontal plane parallel to the rotational axis of the gantry. The couch can rotate through a range 534 of about 270 degrees in the horizontal plane with this configuration. This combination of gantry and patient rotational ranges and degrees of freedom allow the therapist to select virtually any approach angle for the beam. If needed, the patient can be placed on the couch in the opposite orientation and then all possible angles can be used.

In some implementations, the accelerator uses a synchrocyclotron configuration having a very high magnetic field superconducting electromagnetic structure. Because the bend radius of a charged particle of a given kinetic energy is reduced in direct proportion to an increase in the magnetic field applied to it, the very high magnetic field superconducting magnetic structure permits the accelerator to be made smaller and lighter. The synchrocyclotron uses a magnetic field that is uniform in rotation angle and falls off in strength with increasing radius. Such a field shape can be achieved regardless of the magnitude of the magnetic field, so in theory there is no upper limit to the magnetic field strength (and therefore the resulting particle energy at a fixed radius) that can be used in a synchrocyclotron.

Superconducting materials lose their superconducting properties in the presence of very high magnetic fields. High performance superconducting wire windings are used to allow very high magnetic fields to be achieved.

Superconducting materials typically need to be cooled to low temperatures for their superconducting properties to be realized. In some examples described here, cryo-coolers are used to bring the superconducting coil windings to temperatures near absolute zero. Using cryo-coolers can reduce complexity and cost.

The synchrocyclotron is supported on the gantry so that the beam is generated directly in line with the patient. The gantry permits rotation of the cyclotron about a horizontal rotational axis that contains a point (isocenter 540) within, or near, the patient. The split truss that is parallel to the rotational axis, supports the cyclotron on both sides.

Because the rotational range of the gantry is limited, a patient support area can be accommodated in a wide area around the isocenter. Because the floor can be extended broadly around the isocenter, a patient support table can be positioned to move relative to and to rotate about a vertical axis 542 through the isocenter so that, by a combination of gantry rotation and table motion and rotation, any angle of beam direction into any part of the patient can be achieved. The two gantry arms are separated by more than twice the height of a tall patient, allowing the couch with patient to rotate and translate in a horizontal plane above the raised floor.

Limiting the gantry rotation angle allows for a reduction in the thickness of at least one of the walls surrounding the treatment room. Thick walls, typically constructed of concrete, provide radiation protection to individuals outside the treatment room. A wall downstream of a stopping proton beam may be about twice as thick as a wall at the opposite end of the room to provide an equivalent level of protection. Limiting the range of gantry rotation enables the treatment room to be sited below earth grade on three sides, while allowing an occupied area adjacent to the thinnest wall reducing the cost of constructing the treatment room.

In the example implementation shown in FIG. 1, the superconducting synchrocyclotron 502 operates with a peak magnetic field in a pole gap of the synchrocyclotron of 8.8 Tesla. The synchrocyclotron produces a beam of protons having an energy of 250 MeV. In other implementations the field strength could be in the range of 4 to 20 Tesla or 6 to 20 Tesla and the proton energy could be in the range of 150 to 300 MeV

The radiation therapy system described in this example is used for proton radiation therapy, but the same principles and details can be applied in analogous systems for use in heavy ion (ion) treatment systems.

As shown in FIGS. 2, 3, 4, 5, and 6, an example synchrocyclotron 10 (e.g., 502 in FIG. 1) includes a magnet system 12 that contains an particle source 90, a radiofrequency drive system 91, and a beam extraction system 38. The magnetic field established by the magnet system has a shape appropriate to maintain focus of a contained proton beam using a combination of a split pair of annular superconducting coils 40, 42 and a pair of shaped ferromagnetic (e.g., low carbon steel) pole faces 44, 46.

The two superconducting magnet coils are centered on a common axis 47 and are spaced apart along the axis. As shown in FIGS. 7 and 8, the coils are formed by of Nb₃Sn-based superconducting 0.8 mm diameter strands 48 (that initially comprise a niobium-tin core surrounded by a copper sheath) deployed in a twisted cable-in-channel conductor geometry. After seven individual strands are cabled together, they are heated to cause a reaction that forms the final (brittle) superconducting material of the wire. After the material has been reacted, the wires are soldered into the copper channel (outer dimensions 3.18×2.54 mm and inner dimensions 2.08×2.08 mm) and covered with insulation 52 (in this example, a woven fiberglass material). The copper channel containing the wires 53 is then wound in a coil having a rectangular cross-section of 8.55 cm×19.02 cm, having 26 layers and 49 turns per layer. The wound coil is then vacuum impregnated with an epoxy compound. The finished coils are mounted on an annular stainless steel reverse bobbin 56. Heater blankets 55 are placed at intervals in the layers of the windings to protect the assembly in the event of a magnet quench.

The entire coil can then be covered with copper sheets to provide thermal conductivity and mechanical stability and then contained in an additional layer of epoxy. The precompression of the coil can be provided by heating the stainless steel reverse bobbin and fitting the coils within the reverse bobbin. The reverse bobbin inner diameter is chosen so that when the entire mass is cooled to 4 K, the reverse bobbin stays in contact with the coil and provides some compression. Heating the stainless steel reverse bobbin to approximately 50 degrees C. and fitting coils at a temperature of 100 degrees Kelvin can achieve this.

The geometry of the coil is maintained by mounting the coils in a reverse rectangular bobbin 56 to exert a restorative force 60 that works against the distorting force produced when the coils are energized. As shown in FIG. 5, the coil position is maintained relative to the magnet yoke and cryostat using a set of warm-to-cold support straps 402, 404, 406. Supporting the cold mass with thin straps reduces the heat leakage imparted to the cold mass by the rigid support system. The straps are arranged to withstand the varying gravitational force on the coil as the magnet rotates on board the gantry. They withstand the combined effects of gravity and the large de-centering force realized by the coil when it is perturbed from a perfectly symmetric position relative to the magnet yoke. Additionally the links act to reduce dynamic forces imparted on the coil as the gantry accelerates and decelerates when its position is changed. Each warm-to-cold support includes one S2 fiberglass link and one carbon fiber link. The carbon fiber link is supported across pins between the warm yoke and an intermediate temperature (50-70 K), and the S2 fiberglass link 408 is supported across the intermediate temperature pin and a pin attached to the cold mass. Each link is 5 cm long (pin center to pin center) and is 17 mm wide. The link thickness is 9 mm. Each pin is made of high strength stainless steel and is 40 mm in diameter.

Referring to FIG. 3, the field strength profile as a function of radius is determined largely by choice of coil geometry and pole face shape; the pole faces 44, 46 of the permeable yoke material can be contoured to fine tune the shape of the magnetic field to ensure that the particle beam remains focused during acceleration.

The superconducting coils are maintained at temperatures near absolute zero (e.g., about 4 degrees Kelvin) by enclosing the coil assembly (the coils and the bobbin) inside an evacuated annular aluminum or stainless steel cryostatic chamber 70 that provides a free space around the coil structure, except at a limited set of support points 71, 73. In an alternate version (FIG. 4) the outer wall of the cryostat may be made of low carbon steel to provide an additional return flux path for the magnetic field.

In some implementations, the temperature near absolute zero is achieved and maintained using one single-stage Gifford-McMahon cryo-cooler and three two-stage Gifford McMahon cryo-coolers. Each two stage cryo-cooler has a second stage cold end attached to a condenser that recondenses Helium vapor into liquid Helium. The cryo-cooler heads are supplied with compressed Helium from a compressor. The single-stage Gifford-McMahon cryo-cooler is arranged to cool high temperature (e.g., 50-70 degrees Kelvin) leads that supply current to the superconducting windings.

In some implementations, the temperature near absolute zero is achieved and maintained using two Gifford-McMahon cryo-coolers 72, 74 that are arranged at different positions on the coil assembly. Each cryo-cooler has a cold end 76 in contact with the coil assembly. The cryo-cooler heads 78 are supplied with compressed Helium from a compressor 80. Two other Gifford-McMahon cryo-coolers 77, 79 are arranged to cool high temperature (e.g., 60-80 degrees Kelvin) leads that supply current to the superconducting windings.

The coil assembly and cryostatic chambers are mounted within and fully enclosed by two halves 81, 83 of a pillbox-shaped magnet yoke 82. In this example, the inner diameter of the coil assembly is about 74.6 cm. The iron yoke 82 provides a path for the return magnetic field flux 84 and magnetically shields the volume 86 between the pole faces 44, 46 to prevent external magnetic influences from perturbing the shape of the magnetic field within that volume. The yoke also serves to decrease the stray magnetic field in the vicinity of the accelerator. In some implementations, the synchrocyclotron may have an active return system to reduce stray magnetic fields. An example of an active return system is described in U.S. patent application Ser. No. 13/907,601, which was filed on May 31, 2013, the contents of which are incorporated herein by reference. In the active return system, the relatively large magnetic yokes described herein are replaced by smaller magnetic structures, referred to as pole pieces. Superconducting coils run current opposite to the main coils described herein in order to provide magnetic return and thereby reduce stray magnetic fields

As shown in FIGS. 3 and 9, the synchrocyclotron includes a particle source 90 of a Penning ion gauge geometry located near the geometric center 92 of the magnet structure 82. The particle source may be as described below, or the particle source may be of the type described in U.S. patent application Ser. No. 11/948,662 incorporated herein by reference.

Particle source 90 is fed from a supply 99 of hydrogen through a gas line 101 and tube 194 that delivers gaseous hydrogen. Electric cables 94 carry an electric current from a current source 95 to stimulate electron discharge from cathodes 192, 190 that are aligned with the magnetic field, 200.

In some implementations, the gas in gas tube 101 may include a mixture of hydrogen and one or more other gases. For example, the mixture may contain hydrogen and one or more of the noble gases, e.g., helium, neon, argon, krypton, xenon and/or radon (although the mixture is not limited to use with the noble gases). In some implementations, the mixture may be a mixture of hydrogen and helium. For example, the mixture may contain about 75% or more of hydrogen and about 25% or less of helium (with possible trace gases included). In another example, the mixture may contain about 90% or more of hydrogen and about 10% or less of helium (with possible trace gases included). In examples, the hydrogen/helium mixture may be any of the following: >95%/1<5%, >90%/<10%, >85%/<15%, >80%/<20%, >75%/<20%, and so forth.

Possible advantages of using a noble (or other) gas in combination with hydrogen in the particle source may include: increased beam intensity, increased cathode longevity, and increased consistency of beam output.

In this example, the discharged electrons ionize the gas exiting through a small hole from tube 194 to create a supply of positive ions (protons) for acceleration by one semicircular (dee-shaped) radio-frequency plate 100 that spans half of the space enclosed by the magnet structure and one dummy dee plate 102. In the case of an interrupted particle source (an example of which is described in U.S. patent application Ser. No. 11/948,662), all (or a substantial part) of the tube containing plasma is removed at the acceleration region, thereby allowing ions to be more rapidly accelerated in a relatively high magnetic field.

As shown in FIG. 10, the dee plate 100 is a hollow metal structure that has two semicircular surfaces 103, 105 that enclose a space 107 in which the protons are accelerated during half of their rotation around the space enclosed by the magnet structure. A duct 109 opening into the space 107 extends through the yoke to an external location from which a vacuum pump 111 can be attached to evacuate the space 107 and the rest of the space within a vacuum chamber 119 in which the acceleration takes place. The dummy dee 102 comprises a rectangular metal ring that is spaced near to the exposed rim of the dee plate. The dummy dee is grounded to the vacuum chamber and magnet yoke. The dee plate 100 is driven by a radio-frequency signal that is applied at the end of a radio-frequency transmission line to impart an electric field in the space 107. The radio frequency electric field is made to vary in time as the accelerated particle beam increases in distance from the geometric center. The radio frequency electric field may be controlled in the manner described in U.S. patent application Ser. No. 11/948,359, entitled “Matching A Resonant Frequency Of A Resonant Cavity To A Frequency Of An Input Voltage”, the contents of which are incorporated herein by reference.

For the beam emerging from the centrally located particle source to clear the particle source structure as it begins to spiral outward, a large voltage difference is required across the radio frequency plates. 20,000 Volts is applied across the radio frequency plates. In some versions from 8,000 to 20,000 Volts may be applied across the radio frequency plates. To reduce the power required to drive this large voltage, the magnet structure is arranged to reduce the capacitance between the radio frequency plates and ground. This is done by forming holes with sufficient clearance from the radio frequency structures through the outer yoke and the cryostat housing and making sufficient space between the magnet pole faces.

The high voltage alternating potential that drives the dee plate has a frequency that is swept downward during the accelerating cycle to account for the increasing relativistic mass of the protons and the decreasing magnetic field. The dummy dee does not require a hollow semi-cylindrical structure as it is at ground potential along with the vacuum chamber walls. Other plate arrangements could be used such as more than one pair of accelerating electrodes driven with different electrical phases or multiples of the fundamental frequency. The RF structure can be tuned to keep the Q high during the required frequency sweep by using, for example, a rotating capacitor having intermeshing rotating and stationary blades. During each meshing of the blades, the capacitance increases, thus lowering the resonant frequency of the RF structure. The blades can be shaped to create a precise frequency sweep required. A drive motor for the rotating condenser can be phase locked to the RF generator for precise control. One bunch of particles is accelerated during each meshing of the blades of the rotating condenser.

The vacuum chamber 119 in which the acceleration occurs is a generally cylindrical container that is thinner in the center and thicker at the rim. The vacuum chamber encloses the RF plates and the particle source and is evacuated by the vacuum pump 111. Maintaining a high vacuum insures that accelerating ions are not lost to collisions with gas molecules and enables the RF voltage to be kept at a higher level without arcing to ground.

Protons traverse a generally spiral orbital path beginning at the particle source. In half of each loop of the spiral path, the protons gain energy as they pass through the RF electric field in space 107. As the ions gain energy, the radius of the central orbit of each successive loop of their spiral path is larger than the prior loop until the loop radius reaches the maximum radius of the pole face. At that location a magnetic and electric field perturbation directs ions into an area where the magnetic field rapidly decreases, and the ions depart the area of the high magnetic field and are directed through an evacuated tube 38, referred to herein as the extraction channel, to exit the yoke of the cyclotron. A magnetic regenerator may be used to change the magnetic field perturbation to direct the ions. The ions exiting the cyclotron will tend to disperse as they enter the area of markedly decreased magnetic field that exists in the room around the cyclotron. Beam shaping elements 107, 109 in the extraction channel 38 redirect the ions so that they stay in a straight beam of limited spatial extent.

The magnetic field within the pole gap needs to have certain properties to maintain the beam within the evacuated chamber as it accelerates. The magnetic field index n, which is shown below,

n=−(r/B)dB/dr,

should be kept positive to maintain this “weak” focusing. Here r is the radius of the beam and B is the magnetic field. Additionally, in some implementations, the field index needs to be maintained below 0.2, because at this value the periodicity of radial oscillations and vertical oscillations of the beam coincide in a vr=2 v_zresonance. The betatron frequencies are defined by v_r=(1−n)^1/2and v_z=n^1/2. The ferromagnetic pole face is designed to shape the magnetic field generated by the coils so that the field index n is maintained positive and less than 0.2 in the smallest diameter consistent with a 250 MeV beam in the given magnetic field.

As the beam exits the extraction channel it is passed through a beam formation system 125 (FIG. 5) that can be programmably controlled to create a desired combination of scattering angle and range modulation for the beam. Beam formation system 125 may be used in conjunction with an inner gantry 601 (FIG. 14) to direct a beam to the patient.

During operation, the plates absorb energy from the applied radio frequency field as a result of conductive resistance along the surfaces of the plates. This energy appears as heat and is removed from the plates using water cooling lines 108 that release the heat in a heat exchanger 113 (FIG. 3).

Stray magnetic fields exiting from the cyclotron are limited by both the pillbox magnet yoke (which also serves as a shield) and a separate magnetic shield 114. The separate magnetic shield includes of a layer 117 of ferromagnetic material (e.g., steel or iron) that encloses the pillbox yoke, separated by a space 116. This configuration that includes a sandwich of a yoke, a space, and a shield achieves adequate shielding for a given leakage magnetic field at lower weight.

As mentioned, the gantry allows the synchrocyclotron to be rotated about the horizontal rotational axis 532. The truss structure 516 has two generally parallel spans 580, 582. The synchrocyclotron is cradled between the spans about midway between the legs. The gantry is balanced for rotation about the bearings using counterweights 122, 124 mounted on ends of the legs opposite the truss.

The gantry is driven to rotate by an electric motor mounted to one or both of the gantry legs and connected to the bearing housings by drive gears. The rotational position of the gantry is derived from signals provided by shaft angle encoders incorporated into the gantry drive motors and the drive gears.

At the location at which the ion beam exits the cyclotron, the beam formation system 125 acts on the ion beam to give it properties suitable for patient treatment. For example, the beam may be spread and its depth of penetration varied to provide uniform radiation across a given target volume. The beam formation system can include passive scattering elements as well as active scanning elements.

All of the active systems of the synchrocyclotron (the current driven superconducting coils, the RF-driven plates, the vacuum pumps for the vacuum acceleration chamber and for the superconducting coil cooling chamber, the current driven particle source, the hydrogen gas source, and the RF plate coolers, for example), may be controlled by appropriate synchrocyclotron control electronics (not shown), which may include, e.g., one or more computers programmed with appropriate programs to effect control.

The control of the gantry, the patient support, the active beam shaping elements, and the synchrocyclotron to perform a therapy session is achieved by appropriate therapy control electronics (not shown).

As shown in FIGS. 1, 11, and 12, the gantry bearings are supported by the walls of a cyclotron vault 524. The gantry enables the cyclotron to be swung through a range 520 of 180 degrees (or more) including positions above, to the side of, and below the patient. The vault is tall enough to clear the gantry at the top and bottom extremes of its motion. A maze 146 sided by walls 148, 150 provides an entry and exit route for therapists and patients. Because at least one wall 152 is not in line with the proton beam directly from the cyclotron, it can be made relatively thin and still perform its shielding function. The other three side walls 154, 156, 150/148 of the room, which may need to be more heavily shielded, can be buried within an earthen hill (not shown). The required thickness of walls 154, 156, and 158 can be reduced, because the earth can itself provide some of the needed shielding.

Referring to FIGS. 12 and 13, for safety and aesthetic reasons, a therapy room 160 may be constructed within the vault. The therapy room is cantilevered from walls 154, 156, 150 and the base 162 of the containing room into the space between the gantry legs in a manner that clears the swinging gantry and also maximizes the extent of the floor space 164 of the therapy room. Periodic servicing of the accelerator can be accomplished in the space below the raised floor. When the accelerator is rotated to the down position on the gantry, full access to the accelerator is possible in a space separate from the treatment area. Power supplies, cooling equipment, vacuum pumps and other support equipment can be located under the raised floor in this separate space. Within the treatment room, the patient support 170 can be mounted in a variety of ways that permit the support to be raised and lowered and the patient to be rotated and moved to a variety of positions and orientations.

In system 602 of FIG. 14, a beam-producing particle accelerator of the type described herein, in this case synchrocyclotron 604, is mounted on rotating gantry 605. Rotating gantry 605 is of the type described herein, and can angularly rotate around patient support 606. This feature enables synchrocyclotron 604 to provide a particle beam directly to the patient from various angles. For example, as in FIG. 14, if synchrocyclotron 604 is above patient support 606, the particle beam may be directed downwards toward the patient. Alternatively, if synchrocyclotron 604 is below patient support 606, the particle beam may be directed upwards toward the patient. The particle beam is applied directly to the patient in the sense that an intermediary beam routing mechanism is not required. A routing mechanism, in this context, is different from a shaping or sizing mechanism in that a shaping or sizing mechanism does not re-route the beam, but rather sizes and/or shapes the beam while maintaining the same general trajectory of the beam.

Further details regarding an example implementation of the foregoing system may be found in U.S. Pat. No. 7,728,311, filed on Nov. 16, 2006 and entitled “Charged Particle Radiation Therapy”, and in U.S. patent application Ser. No. 12/275,103, filed on Nov. 20, 2008 and entitled “Inner Gantry”. The contents of U.S. Pat. No. 7,728,311 and in U.S. patent application Ser. No. 12/275,103 are hereby incorporated by reference into this disclosure. In some implementations, the synchrocyclotron may be a variable-energy device, such as that described below and in U.S. patent application Ser. No. 13/916,401, filed on Jun. 12, 2013, the contents of which are incorporated herein by reference.

Example Implementations

FIG. 15 shows a top view of a portion of a cavity 700 in which particles are accelerated orbitally (e.g., in outward spiral orbits). A particle source 701, examples of which are described above, is disposed at about the center of the cavity. Charged particles (e.g., protons or ions) are extracted from a plasma column generated by particle source 701. The charged particles accelerate outwardly in orbits toward, and eventually reaching, magnetic field regenerator 702. In this example implementation, regenerator 702 is a single ferromagnetic arrangement made, e.g., of steel, iron, or any other type of ferromagnetic material. Regenerator 702 may include portions thereof connected to respective halves of each magnetic yoke. Regenerator 702 alters the background magnetic field that causes the outward orbital acceleration. In this example, regenerator 702 augments that magnetic field, e.g., it provides a bump in the field by enhancing the magnetic field at its location. The bump in the background magnetic field affects the particle orbits in a way that causes the orbits to move outwardly towards extraction channel 703. Eventually, the orbits enter extraction channel 703, from which they exit.

In more detail, a particle beam orbit approaches and interacts with regenerator 702. As a result of the increased magnetic field, the particle beam turns a bit more there and, instead of being circular, it precesses to the extraction channel. FIG. 16 shows the magnetic field (B) plotted against the radius (r) relative to the particle source 702. As shown in FIG. 16, in this example, B varies from about 9 Tesla (T) to about −2 T. In other implementations, the magnetic field may vary from about 4 T, 5 T, 6 T, 7 T, 8 T, 8.5 T, 9.5 T, 10 T, 105 T, and so forth to −2 T or other values. In this implementation, the 9 T occurs at about the center of cavity 700. The polarity of the magnetic field changes after the magnetic field crosses the superconducting coil, resulting in about −2 T on the exterior of the coil, eventually fading to about zero. The magnetic field bump 705 occurs at the point of the regenerator. FIG. 16 also shows the magnetic field plot relative to a cross-section of a bobbin 706 having extraction channel 703 between two superconducting coils 709, 710.

FIG. 18 shows magnetic effects of the regenerator. More specifically, as shown in FIG. 18, regenerator 702 produces a magnetic field depicted by magnetic field lines 750. Magnetic field lines 750 create a magnetic hole 753 in the background magnetic field. This hole is also depicted in FIG. 16. More specifically, as noted above, FIG. 16 shows magnetic field bump 705 (e.g., 0.5 T to 2 T) produced by regenerator 702, along with the corresponding hole 753 in the background magnetic field. As shown, hole 753 is relatively small in comparison to the background magnetic field. As such, its effect on precession of the orbits is relatively small. As a result, a single regenerator can be used having characteristics similar to those described herein. By contrast, referring to FIG. 19, in a particle accelerator having about 2 T of background magnetic field, the resulting hole 755 would be significant relative to the background magnetic field. Accordingly, progressively smaller ferromagnetic structures are added to produce progressively smaller magnetic field bumps to fill-in hole 755 and additional holes created by the progressively smaller ferromagnetic structures.

In this regard, as explained above, in some implementations, regenerator 702 is a single vertically-aligned ferromagnetic (e.g., steel) arrangement that produces a magnetic field bump of at most 2 T in the presence of a background magnetic field of at least 4 T, 5 T, 6 T (or more, e.g., 7 T, 8 T, 8.5 T, 9.5 T, 10 T, 105 T, and so forth). In some implementations, however, there may be more than one regenerator. Each regenerator may be a progressively smaller, substantially radially-adjacent ferromagnetic arrangement, as shown in FIG. 20, in the presence of magnetic fields of 4 T, 5 T, 6 T or greater (where the radius is from the plasma column outward). In the example of FIG. 20, cavity 760 includes multiple regenerators 761 to 764 relative to plasma column 765. In some implementations, these additional regenerators need not be progressively smaller in size. For example, each one may have the same, or similar size, but may be made of material that produces a smaller magnetic field bump closer to the plasma column. For example, the outermost regenerator relative to the plasma column may have the highest percentage of ferromagnetic material; the next regenerator inward may have a lesser percentage of ferromagnetic material, and so forth. Combinations of size and percentage of ferromagnetic material may be combined to produce the desire effects. Accordingly, the particle accelerator is not limited to use with a regenerator that comprises a single ferromagnetic arrangement, but rather may also be used with multiple, radially-adjacent magnetic field regenerators.

As noted, in some example implementations, a particle accelerator may include multiple regenerators of the type described herein configured and arranged in the orbital cavity to produce one or more magnetic field bumps and/or to shape the magnetic field bump(s). Two or more of these multiple regenerators may be radially-aligned, axially-aligned, or not aligned.

The regenerator may be configured (e.g., shaped and/or moved) to generate a magnetic field bump having any appropriate size (e.g., magnitude) and shape. In some implementations, portions of the regenerator have an irregular cross-sectional shape that is designed to produce a magnetic field bump have a specific shape and/or magnitude. An example of such a cross sectional shape 770 for a portion of regenerator 702 is shown in FIG. 21. There, the cross-sectional irregular shape comprises an angular feature 771 on a portion of the regenerator facing towards the cavity. As shown, angular feature 771 is an edge comprising a non-orthogonal intersection of two faces 772, 773. In other implementations, the cross-sectional shape of a portion of the regenerator may be another irregular shape or may be rectangular, square, curved, trapezoidal, triangular, and so forth. In this example, each cross-section of regenerator 702 is physically connected to a corresponding half yoke 81, 83.

Referring to FIG. 17, regenerator 702 causes changes in the angle 780 and pitch 781 of orbits 710 so that they move toward extraction channel 703. At the point of the extraction channel, the magnetic field strength is sufficiently low to enable the particle beam to enter the extraction channel and to proceed therethrough. Referring back to FIG. 15, extraction channel 703 contains various magnetic structures 711 for adding and/or subtracting dipole fields to direct the entering particle beam through extraction channel 703, to beam shaping elements.

Referring to FIG. 22, in some implementations extraction channel 703 includes a septum 775 near its entry point that separates particles 776 entering the extraction channel from particles 777 remaining in the cavity. The regenerator is configured so that a pitch and an angle of a particle orbit enable a majority of particles in the particle orbit to pass over the septum and into the extraction channel. Particles that hit septum are typically lost. Accordingly, the regenerator may be configured (e.g., shaped and/or moved) to increase the number of particles in a particular orbit that enter the extraction channel and thereby decrease the number of particles that hit the septum. However, in some implementations, even in best case scenarios, there will be particles that hit the septum and that are lost.

In some implementations, regenerator 702 may be moved so that, at different rotational positions, the regenerator affects different particle orbits. The effective magnetic center of the regenerator field bump may also be moved with ferromagnetic elements actuated adjacent to a fixed regenerator. As above, the movement or regenerator 702 or resulting magnetic field perturbation may be computer-controlled through a control system that is part of the particle therapy system. For example, the movement of regenerator 702 may be controlled based on a rotational position of the particle accelerator, as measured by the rotational position of the gantry on which the particle accelerator is mounted. The various parameters used to set the location of the regenerator vis-à-vis the rotational position of the gantry may be measured empirically, and programmed into the control system computer. One or more computer-controlled actuators may effect actual movement of the regenerator.

The regenerator may be moved in any appropriate direction to affect the magnetic field. For example, the regenerator may be moved in the radial direction (e.g., towards or away-from, the particle source). The regenerator may be moved in the Cartesian X, Y and/or Z directions (e.g., length-wise, width-wise or depth-wise) within the cavity in order to provide the appropriate changes to the magnetic field. The regenerator may be rotated relative to its original position to provide the appropriate magnetic field changes.

Variable-Energy Particle Accelerator

The particle accelerator used in the example particle therapy systems described herein may be a variable-energy particle accelerator.

The energy of the extracted particle beam (the particle beam output from the accelerator) can affect the use of the particle beam during treatment. In some machines, the energy of the particle beam (or particles in the particle beam) does not increase after extraction. However, the energy may be reduced based on treatment needs after the extraction and before the treatment. Referring to FIG. 23, an example treatment system 810 includes an accelerator 812, e.g., a synchrocyclotron, from which a particle (e.g., proton) beam 814 having a variable energy is extracted to irradiate a target volume 824 of a body 822. Optionally, one or more additional devices, such as a scanning unit 816 or a scattering unit 816, one or more monitoring units 818, and an energy degrader 820, are placed along the irradiation direction 828. The devices intercept the cross-section of the extracted beam 814 and alter one or more properties of the extracted beam for the treatment.

A target volume to be irradiated (an irradiation target) by a particle beam for treatment typically has a three-dimensional configuration. In some examples, to carry-out the treatment, the target volume is divided into layers along the irradiation direction of the particle beam so that the irradiation can be done on a layer-by-layer basis. For certain types of particles, such as protons, the penetration depth (or which layer the beam reaches) within the target volume is largely determined by the energy of the particle beam. A particle beam of a given energy does not reach substantially beyond a corresponding penetration depth for that energy. To move the beam irradiation from one layer to another layer of the target volume, the energy of the particle beam is changed.

In the example shown in FIG. 23, the target volume 824 is divided into nine layers 826a-826i along the irradiation direction 828. In an example process, the irradiation starts from the deepest layer 826i, one layer at a time, gradually to the shallower layers and finishes with the shallowest layer 826a. Before application to the body 822, the energy of the particle beam 814 is controlled to be at a level to allow the particle beam to stop at a desired layer, e.g., the layer 826d, without substantially penetrating further into the body or the target volume, e.g., the layers 826e-826i or deeper into the body. In some examples, the desired energy of the particle beam 814 decreases as the treatment layer becomes shallower relative to the particle acceleration. In some examples, the beam energy difference for treating adjacent layers of the target volume 824 is about 3 MeV to about 100 MeV, e.g., about 10 MeV to about 80 MeV, although other differences may also be possible, depending on, e.g., the thickness of the layers and the properties of the beam.

The energy variation for treating different layers of the target volume 824 can be performed at the accelerator 812 (e.g., the accelerator can vary the energy) so that, in some implementations, no additional energy variation is required after the particle beam is extracted from the accelerator 812. So, the optional energy degrader 820 in the treatment system 10 may be eliminated from the system. In some implementations, the accelerator 812 can output particle beams having an energy that varies between about 100 MeV and about 300 MeV, e.g., between about 115 MeV and about 250 MeV. The variation can be continuous or non-continuous, e.g., one step at a time. In some implementations, the variation, continuous or non-continuous, can take place at a relatively high rate, e.g., up to about 50 MeV per second or up to about 20 MeV per second. Non-continuous variation can take place one step at a time with a step size of about 10 MeV to about 80 MeV.

When irradiation is complete in one layer, the accelerator 812 can vary the energy of the particle beam for irradiating a next layer, e.g., within several seconds or within less than one second. In some implementations, the treatment of the target volume 824 can be continued without substantial interruption or even without any interruption. In some situations, the step size of the non-continuous energy variation is selected to correspond to the energy difference needed for irradiating two adjacent layers of the target volume 824. For example, the step size can be the same as, or a fraction of, the energy difference.

In some implementations, the accelerator 812 and the degrader 820 collectively vary the energy of the beam 814. For example, the accelerator 812 provides a coarse adjustment and the degrader 820 provides a fine adjustment or vice versa. In this example, the accelerator 812 can output the particle beam that varies energy with a variation step of about 10-80 MeV, and the degrader 820 adjusts (e.g., reduces) the energy of the beam at a variation step of about 2-10 MeV.

The reduced use (or absence) of the energy degrader, which can include range shifters, helps to maintain properties and quality of the output beam from the accelerator, e.g., beam intensity. The control of the particle beam can be performed at the accelerator. Side effects, e.g., from neutrons generated when the particle beam passes the degrader 820 can be reduced or eliminated.

The energy of the particle beam 814 may be adjusted to treat another target volume 830 in another body or body part 822′ after completing treatment in target volume 824. The target volumes 824, 830 may be in the same body (or patient), or may belong to different patients. It is possible that the depth D of the target volume 830 from a surface of body 822′ is different from that of the target volume 824. Although some energy adjustment may be performed by the degrader 820, the degrader 812 may only reduce the beam energy and not increase the beam energy.

In this regard, in some cases, the beam energy required for treating target volume 830 is greater than the beam energy required to treat target volume 824. In such cases, the accelerator 812 may increase the output beam energy after treating the target volume 824 and before treating the target volume 830. In other cases, the beam energy required for treating target volume 830 is less than the beam energy required to treat target volume 824. Although the degrader 820 can reduce the energy, the accelerator 812 can be adjusted to output a lower beam energy to reduce or eliminate the use of the degrader 820. The division of the target volumes 824, 830 into layers can be different or the same. And the target volume 830 can be treated similarly on a layer by layer basis to the treatment of the target volume 824.

The treatment of the different target volumes 824, 830 on the same patient may be substantially continuous, e.g., with the stop time between the two volumes being no longer than about 30 minutes or less, e.g., 25 minutes or less, 20 minutes or less, 15 minutes or less, 10 minutes or less, 5 minutes or less, or 1 minute or less. As is explained herein, the accelerator 812 can be mounted on a movable gantry and the movement of the gantry can move the accelerator to aim at different target volumes. In some situations, the accelerator 812 can complete the energy adjustment of the output beam 814 during the time the treatment system makes adjustment (such as moving the gantry) after completing the treatment of the target volume 824 and before starting treating the target volume 830. After the alignment of the accelerator and the target volume 830 is done, the treatment can begin with the adjusted, desired beam energy. Beam energy adjustment for different patients can also be completed relatively efficiently. In some examples, all adjustments, including increasing/reducing beam energy and/or moving the gantry are done within about 30 minutes, e.g., within about 25 minutes, within about 20 minutes, within about 15 minutes, within about 10 minutes or within about 5 minutes.

In the same layer of a target volume, an irradiation dose is applied by moving the beam across the two-dimensional surface of the layer (which is sometimes called scanning beam) using a scanning unit 816. Alternatively, the layer can be irradiated by passing the extracted beam through one or more scatterers of the scattering unit 16 (which is sometimes called scattering beam).

Beam properties, such as energy and intensity, can be selected before a treatment or can be adjusted during the treatment by controlling the accelerator 812 and/or other devices, such as the scanning unit/scatterer(s) 816, the degrader 820, and others not shown in the figures. In this example implementation, as in the example implementations described above, system 810 includes a controller 832, such as a computer, in communication with one or more devices in the system. Control can be based on results of the monitoring performed by the one or more monitors 818, e.g., monitoring of the beam intensity, dose, beam location in the target volume, etc. Although the monitors 818 are shown to be between the device 816 and the degrader 820, one or more monitors can be placed at other appropriate locations along the beam irradiation path. Controller 832 can also store a treatment plan for one or more target volumes (for the same patient and/or different patients). The treatment plan can be determined before the treatment starts and can include parameters, such as the shape of the target volume, the number of irradiation layers, the irradiation dose for each layer, the number of times each layer is irradiated, etc. The adjustment of a beam property within the system 810 can be performed based on the treatment plan. Additional adjustment can be made during the treatment, e.g., when deviation from the treatment plan is detected.

In some implementations, the accelerator 812 is configured to vary the energy of the output particle beam by varying the magnetic field in which the particle beam is accelerated. In an example implementation, one or more sets of coils receives variable electrical current to produce a variable magnetic field in the cavity. In some examples, one set of coils receives a fixed electrical current, while one or more other sets of coils receives a variable current so that the total current received by the coil sets varies. In some implementations, all sets of coils are superconducting. In other implementations, some sets of coils, such as the set for the fixed electrical current, are superconducting, while other sets of coils, such as the one or more sets for the variable current, are non-superconducting. In some examples, all sets of coils are non-superconducting.

Generally, the magnitude of the magnetic field is scalable with the magnitude of the electrical current. Adjusting the total electric current of the coils in a predetermined range can generate a magnetic field that varies in a corresponding, predetermined range. In some examples, a continuous adjustment of the electrical current can lead to a continuous variation of the magnetic field and a continuous variation of the output beam energy. Alternatively, when the electrical current applied to the coils is adjusted in a non-continuous, step-wise manner, the magnetic field and the output beam energy also varies accordingly in a non-continuous (step-wise) manner. The scaling of the magnetic field to the current can allow the variation of the beam energy to be carried out relatively precisely, although sometimes minor adjustment other than the input current may be performed.

In some implementations, to output particle beams having a variable energy, the accelerator 812 is configured to apply RF voltages that sweep over different ranges of frequencies, with each range corresponding to a different output beam energy. For example, if the accelerator 812 is configured to produce three different output beam energies, the RF voltage is capable of sweeping over three different ranges of frequencies. In another example, corresponding to continuous beam energy variations, the RF voltage sweeps over frequency ranges that continuously change. The different frequency ranges may have different lower frequency and/or upper frequency boundaries.

The extraction channel may be configured to accommodate the range of different energies produced by the variable-energy particle accelerator. Particle beams having different energies can be extracted from the accelerator 812 without altering the features of the regenerator that is used for extracting particle beams having a single energy. In other implementations, to accommodate the variable particle energy, the regenerator can be moved to disturb (e.g., change) different particle orbits in the manner described above and/or iron rods (magnetic shims) can be added or removed to change the magnetic field bump provided by the regenerator. More specifically, different particle energies will typically be at different particle orbits within the cavity. By moving the regenerator in the manner described herein, it is possible to intercept a particle orbit at a specified energy and thereby provide the correct perturbation of that orbit so that particles at the specified energy reach the extraction channel. In some implementations, movement of the regenerator (and/or addition/removal of magnetic shims) is performed in real-time to match real-time changes in the particle beam energy output by the accelerator. In other implementations, particle energy is adjusted on a per-treatment basis, and movement of the regenerator (and/or addition/removal of magnetic shims) is performed in advance of the treatment. In either case, movement of the regenerator (and/or addition/removal of magnetic shims) may be computer controlled. For example, a computer may control one or more motors that effect movement of the regenerator and/or magnetic shims.

In some implementations, the regenerator is implemented using one or more magnetic shims that are controllable to move to the appropriate location(s).

As an example, table 1 shows three example energy levels at which example accelerator 812 can output particle beams. The corresponding parameters for producing the three energy levels are also listed. In this regard, the magnet current refers to the total electrical current applied to the one or more coil sets in the accelerator 812; the maximum and minimum frequencies define the ranges in which the RF voltage sweeps; and “r” is the radial distance of a location to a center of the cavity in which the particles are accelerated.

TABLE 1

Examples of beam energies and respective parameters.

Magnetic
Magnetic

Beam
Magnet
Maximum
Minimum
Field at
Field at

Energy
Current
Frequency
Frequency
r = 0 mm
r = 298 mm

(MeV)
(Amps)
(MHz)
(MHz)
(Tesla)
(Tesla)

250
1990
132
99
8.7
8.2

235
1920
128
97
8.4
8.0

211
1760
120
93
7.9
7.5

Details that may be included in an example particle accelerator that produces charged particles having variable energies are described below. The accelerator can be a synchrocyclotron and the particles may be protons. The particles output as pulsed beams. The energy of the beam output from the particle accelerator can be varied during the treatment of one target volume in a patient, or between treatments of different target volumes of the same patient or different patients. In some implementations, settings of the accelerator are changed to vary the beam energy when no beam (or particles) is output from the accelerator. The energy variation can be continuous or non-continuous over a desired range.

Referring to the example shown in FIG. 1, the particle accelerator (synchrocyclotron 502), which may be a variable-energy particle accelerator like accelerator 812 described above, may be configured to particle beams that have a variable energy. The range of the variable energy can have an upper boundary that is about 200 MeV to about 300 MeV or higher, e.g., 200 MeV, about 205 MeV, about 210 MeV, about 215 MeV, about 220 MeV, about 225 MeV, about 230 MeV, about 235 MeV, about 240 MeV, about 245 MeV, about 250 MeV, about 255 MeV, about 260 MeV, about 265 MeV, about 270 MeV, about 275 MeV, about 280 MeV, about 285 MeV, about 290 MeV, about 295 MeV, or about 300 MeV or higher. The range can also have a lower boundary that is about 100 MeV or lower to about 200 MeV, e.g., about 100 MeV or lower, about 105 MeV, about 110 MeV, about 115 MeV, about 120 MeV, about 125 MeV, about 130 MeV, about 135 MeV, about 140 MeV, about 145 MeV, about 150 MeV, about 155 MeV, about 160 MeV, about 165 MeV, about 170 MeV, about 175 MeV, about 180 MeV, about 185 MeV, about 190 MeV, about 195 MeV, about 200 MeV.

In some examples, the variation is non-continuous and the variation step can have a size of about 10 MeV or lower, about 15 MeV, about 20 MeV, about 25 MeV, about 30 MeV, about 35 MeV, about 40 MeV, about 45 MeV, about 50 MeV, about 55 MeV, about 60 MeV, about 65 MeV, about 70 MeV, about 75 MeV, or about 80 MeV or higher. Varying the energy by one step size can take no more than 30 minutes, e.g., about 25 minutes or less, about 20 minutes or less, about 15 minutes or less, about 10 minutes or less, about 5 minutes or less, about 1 minute or less, or about 30 seconds or less. In other examples, the variation is continuous and the accelerator can adjust the energy of the particle beam at a relatively high rate, e.g., up to about 50 MeV per second, up to about 45 MeV per second, up to about 40 MeV per second, up to about 35 MeV per second, up to about 30 MeV per second, up to about 25 MeV per second, up to about 20 MeV per second, up to about 15 MeV per second, or up to about 10 MeV per second. The accelerator can be configured to adjust the particle energy both continuously and non-continuously. For example, a combination of the continuous and non-continuous variation can be used in a treatment of one target volume or in treatments of different target volumes. Flexible treatment planning and flexible treatment can be achieved.

A particle accelerator that outputs a particle beam having a variable energy can provide accuracy in irradiation treatment and reduce the number of additional devices (other than the accelerator) used for the treatment. For example, the use of degraders for changing the energy of an output particle beam may be reduced or eliminated. The properties of the particle beam, such as intensity, focus, etc. can be controlled at the particle accelerator and the particle beam can reach the target volume without substantial disturbance from the additional devices. The relatively high variation rate of the beam energy can reduce treatment time and allow for efficient use of the treatment system.

In some implementations, the accelerator, such as the synchrocyclotron 502 of FIG. 1, accelerates particles or particle beams to variable energy levels by varying the magnetic field in the accelerator, which can be achieved by varying the electrical current applied to coils for generating the magnetic field. As shown in FIGS. 3, 4, 5, 6, and 7, example synchrocyclotron 10 (502 in FIG. 1) includes a magnet system that contains a particle source 90, a radiofrequency drive system 91, and a beam extraction system 38. FIG. 26 shows an example of a magnet system that may be used in a variable-energy accelerator. In this example implementation, the magnetic field established by the magnet system 1012 can vary by about 5% to about 35% of a maximum value of the magnetic field that two sets of coils 40a and 40b, and 42a and 42b are capable of generating. The magnetic field established by the magnet system has a shape appropriate to maintain focus of a contained proton beam using a combination of the two sets of coils and a pair of shaped ferromagnetic (e.g., low carbon steel) structures, examples of which are provided above.

Each set of coils may be a split pair of annular coils to receive electrical current. In some situations, both sets of coils are superconducting. In other situations, only one set of the coils is superconducting and the other set is non-superconducting or normal conducting (also discussed further below). It is also possible that both sets of coils are non-superconducting. Suitable superconducting materials for use in the coils include niobium-3 tin (Nb3Sn) and/or niobium-titanium. Other normal conducting materials can include copper. Examples of the coil set constructions are described further below.

The two sets of coils can be electrically connected serially or in parallel. In some implementations, the total electrical current received by the two sets of coils can include about 2 million ampere turns to about 10 million ampere turns, e.g., about 2.5 to about 7.5 million ampere turns or about 3.75 million ampere turns to about 5 million ampere turns. In some examples, one set of coils is configured to receive a fixed (or constant) portion of the total variable electrical current, while the other set of coils is configured to receive a variable portion of the total electrical current. The total electrical current of the two coil sets varies with the variation of the current in one coil set. In other situations, the electrical current applied to both sets of coils can vary. The variable total current in the two sets of coils can generate a magnetic field having a variable magnitude, which in turn varies the acceleration pathways of the particles and produces particles having variable energies.

Generally, the magnitude of the magnetic field generated by the coil(s) is scalable to the magnitude of the total electrical current applied to the coil(s). Based on the scalability, in some implementations, linear variation of the magnetic field strength can be achieved by linearly changing the total current of the coil sets. The total current can be adjusted at a relatively high rate that leads to a relatively high-rate adjustment of the magnetic field and the beam energy.

In the example reflected in Table 1 above, the ratio between values of the current and the magnetic field at the geometric center of the coil rings is: 1990:8.7 (approximately 228.7:1); 1920:8.4 (approximately 228.6:1); 1760:7.9 (approximately 222.8:1). Accordingly, adjusting the magnitude of the total current applied to a superconducting coil(s) can proportionally (based on the ratio) adjust the magnitude of the magnetic field.

The scalability of the magnetic field to the total electrical current in the example of Table 1 is also shown in the plot of FIG. 24, where BZ is the magnetic field along the Z direction; and R is the radial distance measured from a geometric center of the coil rings along a direction perpendicular to the Z direction. The magnetic field has the highest value at the geometric center, and decreases as the distance R increases. The curves 1035, 1037 represent the magnetic field generated by the same coil sets receiving different total electrical current: 1760 Amperes and 1990 Amperes, respectively. The corresponding energies of the extracted particles are 211 MeV and 250 MeV, respectively. The two curves 1035, 1037 have substantially the same shape and the different parts of the curves 1035, 1037 are substantially parallel. As a result, either the curve 1035 or the curve 1037 can be linearly shifted to substantially match the other curve, indicating that the magnetic field is scalable to the total electrical current applied to the coil sets.

In some implementations, the scalability of the magnetic field to the total electrical current may not be perfect. For example, the ratio between the magnetic field and the current calculated based on the example shown in table 1 is not constant. Also, as shown in FIG. 24, the linear shift of one curve may not perfectly match the other curve. In some implementations, the total current is applied to the coil sets under the assumption of perfect scalability. The target magnetic field (under the assumption of perfect scalability) can be generated by additionally altering the features, e.g., geometry, of the coils to counteract the imperfection in the scalability. As one example, ferromagnetic (e.g., iron) rods (magnetic shims) can be inserted or removed from one or both of the magnetic structures (e.g., pole pieces). The features of the coils can be altered at a relatively high rate so that the rate of the magnetic field adjustment is not substantially affected as compared to the situation in which the scalability is perfect and only the electrical current needs to be adjusted. In the example of iron rods, the rods can be added or removed at the time scale of seconds or minutes, e.g., within 5 minutes, within 1 minute, less than 30 seconds, or less than 1 second.

In some implementations, settings of the accelerator, such as the current applied to the coil sets, can be chosen based on the substantial scalability of the magnetic field to the total electrical current in the coil sets.

Generally, to produce the total current that varies within a desired range, any combination of current applied to the two coil sets can be used. In an example, the coil set 42a, 42b can be configured to receive a fixed electrical current corresponding to a lower boundary of a desired range of the magnetic field. In the example shown in table 1, the fixed electrical current is 1760 Amperes. In addition, the coil set 40a, 40b can be configured to receive a variable electrical current having an upper boundary corresponding to a difference between an upper boundary and a lower boundary of the desired range of the magnetic field. In the example shown in table 1, the coil set 40a, 40b is configured to receive electrical current that varies between 0 Ampere and 230 Amperes.

In another example, the coil set 42a, 42b can be configured to receive a fixed electrical current corresponding to an upper boundary of a desired range of the magnetic field. In the example shown in table 1, the fixed current is 1990 Amperes. In addition, the coil set 40a, 40b can be configured to receive a variable electrical current having an upper boundary corresponding to a difference between a lower boundary and an upper boundary of the desired range of the magnetic field. In the example shown in table 1, the coil set 40a, 40b is configured to receive electrical current that varies between −230 Ampere and 0 Ampere.

The total variable magnetic field generated by the variable total current for accelerating the particles can have a maximum magnitude greater than 4 Tesla, e.g., greater than 5 Tesla, greater than 6 Tesla, greater than 7 Tesla, greater than 8 Tesla, greater than 9 Tesla, or greater than 10 Tesla, and up to about 20 Tesla or higher, e.g., up to about 18 Tesla, up to about 15 Tesla, or up to about 12 Tesla. In some implementations, variation of the total current in the coil sets can vary the magnetic field by about 0.2 Tesla to about 4.2 Tesla or more, e.g., about 0.2 Tesla to about 1.4 Tesla or about 0.6 Tesla to about 4.2 Tesla. In some situations, the amount of variation of the magnetic field can be proportional to the maximum magnitude.

FIG. 25 shows an example RF structure for sweeping the voltage on the dee plate 100 over an RF frequency range for each energy level of the particle beam, and for varying the frequency range when the particle beam energy is varied. The semicircular surfaces 103, 105 of the dee plate 100 are connected to an inner conductor 1300 and housed in an outer conductor 1302. The high voltage is applied to the dee plate 100 from a power source (not shown, e.g., an oscillating voltage input) through a power coupling device 1304 that couples the power source to the inner conductor. In some implementations, the coupling device 1304 is positioned on the inner conductor 1300 to provide power transfer from the power source to the dee plate 100. In addition, the dee plate 100 is coupled to variable reactive elements 1306, 1308 to perform the RF frequency sweep for each particle energy level, and to change the RF frequency range for different particle energy levels.

The variable reactive element 1306 can be a rotating capacitor that has multiple blades 1310 rotatable by a motor (not shown). By meshing or unmeshing the blades 1310 during each cycle of RF sweeping, the capacitance of the RF structure changes, which in turn changes the resonant frequency of the RF structure. In some implementations, during each quarter cycle of the motor, the blades 1310 mesh with the each other. The capacitance of the RF structure increases and the resonant frequency decreases. The process reverses as the blades 1310 unmesh. As a result, the power required to generate the high voltage applied to the dee plate 103 and necessary to accelerate the beam can be reduced by a large factor. In some implementations, the shape of the blades 1310 is machined to form the required dependence of resonant frequency on time.

The RF frequency generation is synchronized with the blade rotation by sensing the phase of the RF voltage in the resonator, keeping the alternating voltage on the dee plates close to the resonant frequency of the RF cavity. (The dummy dee is grounded and is not shown in FIG. 25).

The variable reactive element 1308 can be a capacitor formed by a plate 1312 and a surface 1316 of the inner conductor 1300. The plate 1312 is movable along a direction 1314 towards or away from the surface 1316. The capacitance of the capacitor changes as the distance D between the plate 1312 and the surface 1316 changes. For each frequency range to be swept for one particle energy, the distance D is at a set value, and to change the frequency range, the plate 1312 is moved corresponding to the change in the energy of the output beam.

In some implementations, the inner and outer conductors 1300, 1302 are formed of a metallic material, such as copper, aluminum, or silver. The blades 1310 and the plate 1312 can also be formed of the same or different metallic materials as the conductors 1300, 1302. The coupling device 1304 can be an electrical conductor. The variable reactive elements 1306, 1308 can have other forms and can couple to the dee plate 100 in other ways to perform the RF frequency sweep and the frequency range alteration. In some implementations, a single variable reactive element can be configured to perform the functions of both the variable reactive elements 1306, 1308. In other implementations, more than two variable reactive elements can be used.

Any two more of the foregoing implementations may be used in an appropriate combination in an appropriate particle accelerator (e.g., a synchrocyclotron). Likewise, individual features of any two more of the foregoing implementations may be used in an appropriate combination.

Elements of different implementations described herein may be combined to form other implementations not specifically set forth above. Elements may be left out of the processes, systems, apparatus, etc., described herein without adversely affecting their operation. Various separate elements may be combined into one or more individual elements to perform the functions described herein.

The example implementations described herein are not limited to use with a particle therapy system or to use with the example particle therapy systems described herein. Rather, the example implementations can be used in any appropriate system that directs accelerated particles to an output.

Additional information concerning the design of an example implementation of a particle accelerator that may be used in a system as described herein can be found in U.S. Provisional Application No. 60/760,788, entitled “High-Field Superconducting Synchrocyclotron” and filed Jan. 20, 2006; U.S. patent application Ser. No. 11/463,402, entitled “Magnet Structure For Particle Acceleration” and filed Aug. 9, 2006; and U.S. Provisional Application No. 60/850,565, entitled “Cryogenic Vacuum Break Pneumatic Thermal Coupler” and filed Oct. 10, 2006, all of which are incorporated herein by reference.

The following applications are incorporated by reference into the subject application: the U.S. Provisional Application entitled “CONTROLLING INTENSITY OF A PARTICLE BEAM” (Application No. 61/707,466), the U.S. Provisional Application entitled “ADJUSTING ENERGY OF A PARTICLE BEAM” (Application No. 61/707,515), the U.S. Provisional Application entitled “ADJUSTING COIL POSITION” (Application No. 61/707,548), the U.S. Provisional Application entitled “FOCUSING A PARTICLE BEAM USING MAGNETIC FIELD FLUTTER” (Application No. 61/707,572), the U.S. Provisional Application entitled “MAGNETIC FIELD REGENERATOR” (Application No. 61/707,590), the U.S. Provisional Application entitled “FOCUSING A PARTICLE BEAM” (Application No. 61/707,704), the U.S. Provisional Application entitled “CONTROLLING PARTICLE THERAPY (Application No. 61/707,624), and the U.S. Provisional Application entitled “CONTROL SYSTEM FOR A PARTICLE ACCELERATOR” (Application No. 61/707,645).

The following are also incorporated by reference into the subject application: U.S. Pat. No. 7,728,311 which issued on Jun. 1, 2010, U.S. patent application Ser. No. 11/948,359 which was filed on Nov. 30, 2007, U.S. patent application Ser. No. 12/275,103 which was filed on Nov. 20, 2008, U.S. patent application Ser. No. 11/948,662 which was filed on Nov. 30, 2007, U.S. Provisional Application No. 60/991,454 which was filed on Nov. 30, 2007, U.S. Pat. No. 8,003,964 which issued on Aug. 23, 2011, U.S. Pat. No. 7,208,748 which issued on Apr. 24, 2007, U.S. Pat. No. 7,402,963 which issued on Jul. 22, 2008, U.S. patent application Ser. No. 13/148,000 filed Feb. 9, 2010, U.S. patent application Ser. No. 11/937,573 filed on Nov. 9, 2007, U.S. patent application Ser. No. 11/187,633, titled “A Programmable Radio Frequency Waveform Generator for a Synchrocyclotron,” filed Jul. 21, 2005, U.S. Provisional Application No. 60/590,089, filed on Jul. 21, 2004, U.S. patent application Ser. No. 10/949,734, titled “A Programmable Particle Scatterer for Radiation Therapy Beam Formation”, filed Sep. 24, 2004, and U.S. Provisional Application No. 60/590,088, filed Jul. 21, 2005.

Any features of the subject application may be combined with one or more appropriate features of the following: the U.S. Provisional Application entitled “CONTROLLING INTENSITY OF A PARTICLE BEAM” (Application No. 61/707,466), the U.S. Provisional Application entitled “ADJUSTING ENERGY OF A PARTICLE BEAM” (Application No. 61/707,515), the U.S. Provisional Application entitled “ADJUSTING COIL POSITION” (Application No. 61/707,548), the U.S. Provisional Application entitled “FOCUSING A PARTICLE BEAM USING MAGNETIC FIELD FLUTTER” (Application No. 61/707,572), the U.S. Provisional Application entitled “MAGNETIC FIELD REGENERATOR” (Application No. 61/707,590), the U.S. Provisional Application entitled “FOCUSING A PARTICLE BEAM” (Application No. 61/707,704), the U.S. Provisional Application entitled “CONTROLLING PARTICLE THERAPY (Application No. 61/707,624), and the U.S. Provisional Application entitled “CONTROL SYSTEM FOR A PARTICLE ACCELERATOR” (Application No. 61/707,645), U.S. Pat. No. 7,728,311 which issued on Jun. 1, 2010, U.S. patent application Ser. No. 11/948,359 which was filed on Nov. 30, 2007, U.S. patent application Ser. No. 12/275,103 which was filed on Nov. 20, 2008, U.S. patent application Ser. No. 11/948,662 which was filed on Nov. 30, 2007, U.S. Provisional Application No. 60/991,454 which was filed on Nov. 30, 2007, U.S. patent application Ser. No. 13/907,601, which was filed on May 31, 2013, U.S. patent application Ser. No. 13/916,401, filed on Jun. 12, 2013, U.S. Pat. No. 8,003,964 which issued on Aug. 23, 2011, U.S. Pat. No. 7,208,748 which issued on Apr. 24, 2007, U.S. Pat. No. 7,402,963 which issued on Jul. 22, 2008, U.S. patent application Ser. No. 13/148,000 filed Feb. 9, 2010, U.S. patent application Ser. No. 11/937,573 filed on Nov. 9, 2007, U.S. patent application Ser. No. 11/187,633, titled “A Programmable Radio Frequency Waveform Generator for a Synchrocyclotron,” filed Jul. 21, 2005, U.S. Provisional Application No. 60/590,089, filed on Jul. 21, 2004, U.S. patent application Ser. No. 10/949,734, titled “A Programmable Particle Scatterer for Radiation Therapy Beam Formation”, filed Sep. 24, 2004, and U.S. Provisional Application No. 60/590,088, filed Jul. 21, 2005.

Except for the provisional application from which this patent application claims priority and the documents incorporated by reference above, no other documents are incorporated by reference into this patent application.

Other implementations not specifically described herein are also within the scope of the following claims.

Claims

1. A particle accelerator comprising: a voltage source to provide a radio frequency (RF) voltage to a cavity to accelerate particles within the cavity, the cavity having a magnetic field causing the particles to move orbitally within the cavity;an extraction channel to receive the particles from the cavity and to output the received particles from the cavity; anda regenerator to provide a magnetic field change within the cavity to thereby change orbits of particles within the cavity so that, eventually, the particles output to the extraction channel, the regenerator comprising an edge comprising a non-orthogonal intersection of two faces;wherein the magnetic field in a center of the cavity is at least 6 Tesla.
2. The particle accelerator of claim 1, wherein the regenerator comprises a ferromagnetic arrangement located at a radial location from a center of the cavity.
3. The particle accelerator of claim 2, wherein the regenerator comprises a single ferromagnetic arrangement.
4. The particle accelerator of claim 1, wherein the regenerator includes steel.
5. The particle accelerator of claim 1, wherein the magnetic field is at most 20 Tesla and the magnetic field change comprises a magnetic field bump that is at most 2 Tesla.
6. The particle accelerator of claim 1, wherein the magnetic field change comprises a magnetic field bump; and wherein the regenerator is designed to produce the magnetic field bump IQ have a specific shape and/or magnitude that is based on a number of the particles to enter the extraction channel.
7. The particle accelerator of claim 1, wherein the edge comprises a single edge that faces toward a center of the cavity.
8. The particle accelerator of claim 1, wherein the extraction channel comprises a septum that separates the particles entering the extraction channel from other particles, the regenerator being configured so that a pitch and an angle of a particle orbit enable a majority of particles in the particle orbit to pass over the septum and into the extraction channel.
9. The particle accelerator of claim 8, wherein the particles passing over the septum are within a range of orbits of particles relative to a center of the cavity.
10. A proton therapy system comprising: the particle accelerator of claim 1; anda gantry on which the particle accelerator is mounted, the gantry being rotatable relative to a patient position;wherein the particles comprise protons that are output essentially directly from the particle accelerator to the patient position.
11. The proton therapy system of claim 10, wherein the particle accelerator comprises a synchrocyclotron.
12. The particle accelerator of claim 11, wherein the particles received by the extraction channel from the cavity comprise less than all particles in the orbit.
13. The particle accelerator of claim 1, wherein the two faces are not parallel to, or perpendicular to, a mid-plane of the particle accelerator.
14. The particle accelerator of claim 13, wherein the regenerator is movable within the cavity.
15. The particle accelerator of claim 14, wherein the regenerator is movable towards or away from a center of the cavity.
16. The particle accelerator of claim 11, wherein the particles output to the extraction channel comprise less than all particles in an orbit.
17. A particle accelerator comprising: a particle source to provide particles to a cavity;a voltage source to provide a radio frequency (RF) voltage to the cavity to accelerate the particles within the cavity, the particles accelerated within the cavity traveling in an orbit within the cavity;an extraction channel to receive the particles from the cavity for output from the particle accelerator; anda regenerator to provide a magnetic field bump within the cavity to change the orbit of the particles in order to direct the particles in the orbit toward the extraction channel, the regenerator comprising intersecting faces that are not parallel to, or perpendicular to, a mid-plane of the particle accelerator.
18. The particle accelerator of claim 17, wherein a magnetic field in a center of the cavity is at least 4 Tesla.
19. The particle accelerator of claim 17, wherein the magnetic field bump is at most 2 Tesla.
20. The particle accelerator of claim 17, wherein the regenerator is movable in one or more dimensions relative to a center of the cavity.
21. The particle accelerator of claim 17, wherein the regenerator is designed to produce the magnetic field bump to have a specific shape and/or magnitude that is based on a number of the particles to enter the extraction channel.
22. The particle accelerator of claim 21, wherein a magnetic field in a center of the cavity is at least 6 Tesla.
23. The particle accelerator of claim 17, wherein the extraction channel comprises a septum that separates the particles entering the extraction channel from other particles, the regenerator being configured so that a pitch and an angle of the orbit enable a majority of the particles in the orbit to pass over the septum and into the extraction channel.
24. The particle accelerator of claim 17, wherein particles that pass over the septum are within a range of orbits of particles relative to a center of the cavity.
25. A proton therapy system comprising: the particle accelerator of claim 17; anda gantry on which the particle accelerator is mounted, the gantry being rotatable relative to a patient position;wherein the particles comprise protons that are output essentially directly from the particle accelerator to the patient position.
26. The proton therapy system of claim 25, wherein the particle accelerator comprises a synchrocyclotron.
27. A particle accelerator comprising: a voltage source to provide a radio frequency (RF) voltage to a cavity to accelerate particles within the cavity, the cavity having a magnetic field causing the particles accelerated to move orbitally within the cavity;an extraction channel to receive at least some of the particles accelerated and to output the at least some of the particles from the cavity; anda regenerator to change a magnetic field within the cavity to thereby change successive orbits of the particles accelerated so that, eventually, the at least some of the particles output to the extraction channel, the regenerator comprising an edge formed by a non-orthogonal intersection of two faces, where the two faces are not parallel to, or perpendicular to, a mid-plane of the particle accelerator.
28. The particle accelerator of claim 18, wherein the regenerator is movable within the cavity.
29. The particle accelerator of claim 28, wherein the regenerator is movable towards or away from a center of the cavity.
30. The particle accelerator of claim 18, wherein the faces intersect at an edge that faces an interior of the cavity.
31. The particle accelerator of claim 27, wherein the particle accelerator is configured to vary an energy of the particles that move orbitally within the cavity; and wherein the regenerator is movable in one or more dimensions within the cavity, where movement of the regenerator is based on an energy of the particles.
32. The particle accelerator of claim 11, further comprising: coils to pass current to generate the magnetic field, wherein a variation in an amount of current through the coils corresponds to a variation in an energy of the particles.
33. The particle accelerator of claim 31, further comprising: an energy degrader to affect an energy of a particle beam output from the particle accelerator.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No. 14/039,652, which was filed on Sep. 27, 2013 and which issued as U.S. Pat. No. 9,622,334 on Apr. 11, 2017. Priority is hereby claimed to U.S. patent application Ser. No. 14/039,652. The contents of U.S. patent application Ser. No. 14/039,652 are incorporated by reference into this disclosure. Priority is hereby also claimed to U.S. Provisional Application No. 61/707,590, which was filed on Sep. 28, 2012. The contents of U.S. Provisional Application No. 61/707,590 are hereby incorporated by reference into this disclosure.

US Referenced Citations (622)

Number	Name	Date	Kind
498915	Heimann	Jun 1893	A
2280606	Roberts	Apr 1942	A
2492324	Salisbury	Dec 1949	A
2615129	McMillan	Oct 1952	A
2616042	Weeks	Oct 1952	A
2626351	Powell	Jan 1953	A
2659000	Salisbury	Nov 1953	A
2701304	Dickinson	Feb 1955	A
2789222	Martin et al.	Apr 1957	A
2812463	Teng et al.	Nov 1957	A
2958327	Geissmann	Nov 1960	A
3024379	Verster	Mar 1962	A
3175131	Burleigh et al.	Mar 1965	A
3398308	Steimel	Aug 1968	A
3432721	Naydan et al.	Mar 1969	A
3582650	Avery	Jun 1971	A
3679899	Dimeff	Jul 1972	A
3689847	Verster	Sep 1972	A
3757118	Hodge et al.	Sep 1973	A
3868522	Bigham et al.	Feb 1975	A
3883761	Hendry	May 1975	A
3886367	Castle, Jr.	May 1975	A
3925676	Bigham et al.	Dec 1975	A
3955089	McIntyre et al.	May 1976	A
3958327	Marancik et al.	May 1976	A
3992625	Schmidt et al.	Nov 1976	A
4038622	Purcell	Jul 1977	A
4047068	Ress et al.	Sep 1977	A
4095201	Kervizic et al.	Jun 1978	A
4112306	Nunan	Sep 1978	A
4129784	Tschunt et al.	Dec 1978	A
4139777	Rautenbach	Feb 1979	A
4197510	Szu	Apr 1980	A
4220866	Taumann et al.	Sep 1980	A
4230129	LeVeen	Oct 1980	A
4256966	Heinz	Mar 1981	A
4293772	Stieber	Oct 1981	A
4336505	Meyer	Jun 1982	A
4342060	Gibson	Jul 1982	A
4345210	Tran	Aug 1982	A
4353033	Karasawa	Oct 1982	A
4425506	Brown et al.	Jan 1984	A
4490616	Cipollina et al.	Dec 1984	A
4507614	Prono et al.	Mar 1985	A
4507616	Blosser et al.	Mar 1985	A
4589126	Augustsson et al.	May 1986	A
4598208	Brunelli et al.	Jul 1986	A
4628523	Heflin	Dec 1986	A
4633125	Blosser et al.	Dec 1986	A
4641057	Blosser et al.	Feb 1987	A
4641104	Blosser et al.	Feb 1987	A
4651007	Perusek et al.	Mar 1987	A
4680565	Jahnke	Jul 1987	A
4705955	Mileikowsky	Nov 1987	A
4710722	Jahnke	Dec 1987	A
4726046	Nunan	Feb 1988	A
4734653	Jahnke	Mar 1988	A
4736173	Basil, Jr. et al.	Apr 1988	A
4737727	Yamada et al.	Apr 1988	A
4739173	Blosser et al.	Apr 1988	A
4745367	Dustmann et al.	May 1988	A
4754147	Maughan et al.	Jun 1988	A
4763483	Olsen	Aug 1988	A
4767930	Stieber et al.	Aug 1988	A
4769623	Marsing et al.	Sep 1988	A
4771208	Jongen et al.	Sep 1988	A
4783634	Yamamoto et al.	Nov 1988	A
4808941	Marsing	Feb 1989	A
4812658	Koehler	Mar 1989	A
4843333	Marsing et al.	Jun 1989	A
4845371	Stieber	Jul 1989	A
4865284	Gosis et al.	Sep 1989	A
4868843	Nunan	Sep 1989	A
4868844	Nunan	Sep 1989	A
4870287	Cole et al.	Sep 1989	A
4880985	Jones	Nov 1989	A
4894541	Ono	Jan 1990	A
4896206	Denham	Jan 1990	A
4902993	Krevet	Feb 1990	A
4904949	Wilson	Feb 1990	A
4905267	Miller et al.	Feb 1990	A
4917344	Prechter et al.	Apr 1990	A
4943781	Wilson et al.	Jul 1990	A
4945478	Merickel et al.	Jul 1990	A
4987309	Klasen et al.	Jan 1991	A
4992744	Fujita et al.	Feb 1991	A
4996496	Kitamura et al.	Feb 1991	A
5006759	Krispel	Apr 1991	A
5010562	Hernandez et al.	Apr 1991	A
5012111	Ueda	Apr 1991	A
5017789	Young et al.	May 1991	A
5017882	Finlan	May 1991	A
5036290	Sonobe et al.	Jul 1991	A
5039057	Prechter et al.	Aug 1991	A
5039867	Nishihara et al.	Aug 1991	A
5046078	Hernandez et al.	Sep 1991	A
5072123	Johnsen	Dec 1991	A
5111042	Sullivan et al.	May 1992	A
5111173	Matsuda et al.	May 1992	A
5117194	Nakanishi et al.	May 1992	A
5117212	Yamamoto et al.	May 1992	A
5117829	Miller et al.	Jun 1992	A
5148032	Hernandez	Sep 1992	A
5166531	Huntzinger	Nov 1992	A
5189687	Bova et al.	Feb 1993	A
5191706	Cosden	Mar 1993	A
5240218	Dye	Aug 1993	A
5260579	Yasuda et al.	Nov 1993	A
5260581	Lesyna et al.	Nov 1993	A
5278533	Kawaguchi	Jan 1994	A
5285166	Hiramoto et al.	Feb 1994	A
5317164	Kurokawa	May 1994	A
5336891	Crewe	Aug 1994	A
5341104	Anton et al.	Aug 1994	A
5349198	Takanaka	Sep 1994	A
5365742	Boffito et al.	Nov 1994	A
5374913	Pissantezky et al.	Dec 1994	A
5382914	Hamm et al.	Jan 1995	A
5401973	McKeown et al.	Mar 1995	A
5405235	Lebre et al.	Apr 1995	A
5434420	McKeown et al.	Jul 1995	A
5440133	Moyers et al.	Aug 1995	A
5451794	McKeown et al.	Sep 1995	A
5461773	Kawaguchi	Oct 1995	A
5463291	Carroll et al.	Oct 1995	A
5464411	Schulte et al.	Nov 1995	A
5492922	Palkowitz	Feb 1996	A
5511549	Legg et al.	Apr 1996	A
5521469	Laisne	May 1996	A
5538942	Koyama et al.	Jul 1996	A
5549616	Schulte et al.	Aug 1996	A
5561697	Takafuji et al.	Oct 1996	A
5585642	Britton et al.	Dec 1996	A
5633747	Nikoonahad	May 1997	A
5635721	Bardi et al.	Jun 1997	A
5668371	Deasy et al.	Sep 1997	A
5672878	Yao	Sep 1997	A
5691679	Ackermann et al.	Nov 1997	A
5717371	Crow	Feb 1998	A
5726448	Smith et al.	Mar 1998	A
5727554	Kalend et al.	Mar 1998	A
5730745	Schulte et al.	Mar 1998	A
5739646	Nakanishi et al.	Apr 1998	A
5751781	Brown et al.	May 1998	A
5778047	Mansfield et al.	Jul 1998	A
5783914	Hiramoto et al.	Jul 1998	A
5784431	Kalend et al.	Jul 1998	A
5797924	Schulte et al.	Aug 1998	A
5811944	Sampayan et al.	Sep 1998	A
5818058	Nakanishi et al.	Oct 1998	A
5821705	Caporaso et al.	Oct 1998	A
5825845	Blair et al.	Oct 1998	A
5841237	Alton	Nov 1998	A
5846043	Spath	Dec 1998	A
5851182	Sahadevan	Dec 1998	A
5866912	Slater et al.	Feb 1999	A
5874811	Finlan et al.	Feb 1999	A
5895926	Britton et al.	Apr 1999	A
5920601	Nigg et al.	Jul 1999	A
5929458	Nemezawa et al.	Jul 1999	A
5963615	Egley et al.	Oct 1999	A
5993373	Nonaka et al.	Nov 1999	A
6008499	Hiramoto et al.	Dec 1999	A
6034377	Pu	Mar 2000	A
6057655	Jongen	May 2000	A
6061426	Linders et al.	May 2000	A
6064807	Arai et al.	May 2000	A
6066851	Madono et al.	May 2000	A
6080992	Nonaka et al.	Jun 2000	A
6087670	Hiramoto et al.	Jul 2000	A
6094760	Nonaka et al.	Aug 2000	A
6118848	Reiffel	Sep 2000	A
6140021	Nakasuji et al.	Oct 2000	A
6144875	Schweikard et al.	Nov 2000	A
6158708	Egley et al.	Dec 2000	A
6207952	Kan et al.	Mar 2001	B1
6219403	Nishihara	Apr 2001	B1
6222905	Yoda et al.	Apr 2001	B1
6241671	Ritter et al.	Jun 2001	B1
6246066	Yuehu	Jun 2001	B1
6256591	Yoda et al.	Jul 2001	B1
6265837	Akiyama et al.	Jul 2001	B1
6268610	Pu	Jul 2001	B1
6278239	Caporaso et al.	Aug 2001	B1
6279579	Riaziat et al.	Aug 2001	B1
6307914	Kunieda et al.	Oct 2001	B1
6316776	Hiramoto et al.	Nov 2001	B1
6366021	Meddaugh et al.	Apr 2002	B1
6369585	Yao	Apr 2002	B2
6380545	Yan	Apr 2002	B1
6407505	Bertsche	Jun 2002	B1
6417634	Bergstrom	Jul 2002	B1
6433336	Jongen et al.	Aug 2002	B1
6433349	Akiyama et al.	Aug 2002	B2
6433494	Kulish et al.	Aug 2002	B1
6441569	Janzow	Aug 2002	B1
6443349	Van Der Burg	Sep 2002	B1
6465957	Whitham et al.	Oct 2002	B1
6472834	Hiramoto et al.	Oct 2002	B2
6476403	Dolinskii et al.	Nov 2002	B1
6492922	New	Dec 2002	B1
6493424	Whitham	Dec 2002	B2
6498444	Hanna et al.	Dec 2002	B1
6501961	Kirkpatrick	Dec 2002	B1
6501981	Schweikard et al.	Dec 2002	B1
6519316	Collins	Feb 2003	B1
6594336	Nishizawa et al.	Jul 2003	B2
6600164	Badura et al.	Jul 2003	B1
6617598	Matsuda	Sep 2003	B1
6621889	Mostafavi	Sep 2003	B1
6639234	Badura et al.	Oct 2003	B1
6646383	Bertsche et al.	Nov 2003	B2
6670618	Hartmann et al.	Dec 2003	B1
6683318	Haberer et al.	Jan 2004	B1
6683426	Kleeven	Jan 2004	B1
6693283	Eickhoff et al.	Feb 2004	B2
6710362	Kraft et al.	Mar 2004	B2
6713773	Lyons et al.	Mar 2004	B1
6713976	Zumoto et al.	Mar 2004	B1
6717162	Jongen	Apr 2004	B1
6736831	Hartmann et al.	May 2004	B1
6745072	Badura et al.	Jun 2004	B1
6769806	Moyers	Aug 2004	B2
6774383	Norimine et al.	Aug 2004	B2
6777689	Nelson	Aug 2004	B2
6777700	Yanagisawa et al.	Aug 2004	B2
6780149	Schulte	Aug 2004	B1
6794868	Wong et al.	Sep 2004	B1
6799068	Hartmann et al.	Sep 2004	B1
6800866	Amemiya et al.	Oct 2004	B2
6803591	Muramatsu et al.	Oct 2004	B2
6814694	Pedroni	Nov 2004	B1
6822244	Beloussov et al.	Nov 2004	B2
6853142	Chistyakov	Feb 2005	B2
6853703	Svatos et al.	Feb 2005	B2
6864770	Nemoto et al.	Mar 2005	B2
6865254	Nafstadius	Mar 2005	B2
6873123	Marchand et al.	Mar 2005	B2
6891177	Kraft et al.	May 2005	B1
6891924	Yoda et al.	May 2005	B1
6894300	Reimoser et al.	May 2005	B2
6897451	Kaercher et al.	May 2005	B2
6914396	Symons et al.	Jul 2005	B1
6936832	Norimine et al.	Aug 2005	B2
6953943	Yanagisawa et al.	Oct 2005	B2
6965116	Wagner et al.	Nov 2005	B1
6969194	Nafstadius	Nov 2005	B1
6979832	Yanagisawa et al.	Dec 2005	B2
6984835	Harada	Jan 2006	B2
6992312	Yanagisawa et al.	Jan 2006	B2
6993112	Hesse	Jan 2006	B2
7008105	Amann et al.	Mar 2006	B2
7011447	Moyers	Mar 2006	B2
7012267	Moriyama et al.	Mar 2006	B2
7014361	Ein-Gal	Mar 2006	B1
7026636	Yanagisawa et al.	Apr 2006	B2
7038403	Mastrangeli et al.	May 2006	B2
7041479	Swartz et al.	May 2006	B2
7045781	Adamec et al.	May 2006	B2
7049613	Yanagisawa et al.	May 2006	B2
7053389	Yanagisawa et al.	May 2006	B2
7054801	Sakamoto et al.	May 2006	B2
7060997	Norimine et al.	Jun 2006	B2
7071479	Yanagisawa et al.	Jul 2006	B2
7073508	Moyers	Jul 2006	B2
7081619	Bashkirov et al.	Jul 2006	B2
7084410	Beloussov et al.	Aug 2006	B2
7091478	Haberer	Aug 2006	B2
7102144	Matsuda et al.	Sep 2006	B2
7122811	Matsuda et al.	Oct 2006	B2
7122966	Norling et al.	Oct 2006	B2
7135678	Wang et al.	Nov 2006	B2
7138771	Bechthold et al.	Nov 2006	B2
7154107	Yanagisawa et al.	Dec 2006	B2
7154108	Tadokoro et al.	Dec 2006	B2
7154991	Earnst et al.	Dec 2006	B2
7162005	Bjorkholm	Jan 2007	B2
7173264	Moriyama et al.	Feb 2007	B2
7173265	Miller et al.	Feb 2007	B2
7173385	Caporaso et al.	Feb 2007	B2
7186991	Kato et al.	Mar 2007	B2
7193227	Hiramoto et al.	Mar 2007	B2
7199382	Rigney et al.	Apr 2007	B2
7208748	Sliski et al.	Apr 2007	B2
7212608	Nagamine et al.	May 2007	B2
7212609	Nagamine et al.	May 2007	B2
7221733	Takai et al.	May 2007	B1
7227161	Matsuda et al.	Jun 2007	B2
7247869	Tadokoro et al.	Jul 2007	B2
7257191	Sommer	Aug 2007	B2
7259529	Tanaka	Aug 2007	B2
7262424	Moriyama et al.	Aug 2007	B2
7262565	Fujisawa	Aug 2007	B2
7274018	Adamec et al.	Sep 2007	B2
7280633	Cheng et al.	Oct 2007	B2
7295649	Johnsen	Nov 2007	B2
7297967	Yanagisawa et al.	Nov 2007	B2
7301162	Matsuda et al.	Nov 2007	B2
7307264	Brusasco et al.	Dec 2007	B2
7318805	Schweikard et al.	Jan 2008	B2
7319231	Moriyama et al.	Jan 2008	B2
7319336	Baur et al.	Jan 2008	B2
7331713	Moyers	Feb 2008	B2
7332880	Ina et al.	Feb 2008	B2
7345291	Kats	Mar 2008	B2
7345292	Moriyama et al.	Mar 2008	B2
7348557	Armit	Mar 2008	B2
7348579	Pedroni	Mar 2008	B2
7351988	Naumann et al.	Apr 2008	B2
7355189	Yanagisawa et al.	Apr 2008	B2
7368740	Beloussov et al.	May 2008	B2
7372053	Yamashita et al.	May 2008	B2
7378672	Harada	May 2008	B2
7381979	Yamashita et al.	Jun 2008	B2
7397054	Natori et al.	Jul 2008	B2
7397901	Johnsen	Jul 2008	B1
7398309	Baumann et al.	Jul 2008	B2
7402822	Guertin et al.	Jul 2008	B2
7402823	Guertin et al.	Jul 2008	B2
7402824	Guertin et al.	Jul 2008	B2
7402963	Sliski et al.	Jul 2008	B2
7405407	Hiramoto et al.	Jul 2008	B2
7425717	Matsuda et al.	Sep 2008	B2
7432516	Peggs et al.	Oct 2008	B2
7439528	Nishiuchi et al.	Oct 2008	B2
7446328	Rigney et al.	Nov 2008	B2
7446490	Jongen et al.	Nov 2008	B2
7449701	Fujimaki et al.	Nov 2008	B2
7453076	Welch et al.	Nov 2008	B2
7465944	Ueno et al.	Dec 2008	B2
7466085	Nutt	Dec 2008	B2
7468506	Rogers et al.	Dec 2008	B2
7473913	Hermann et al.	Jan 2009	B2
7476867	Fritsch et al.	Jan 2009	B2
7476883	Nutt	Jan 2009	B2
7482606	Groezinger et al.	Jan 2009	B2
7492556	Atkins et al.	Feb 2009	B2
7507975	Mohr	Mar 2009	B2
7525104	Harada	Apr 2009	B2
7541905	Antaya	Jun 2009	B2
7547901	Guertin et al.	Jun 2009	B2
7554096	Ward et al.	Jun 2009	B2
7554097	Ward et al.	Jun 2009	B2
7555103	Johnsen	Jun 2009	B2
7557358	Ward et al.	Jul 2009	B2
7557359	Ward et al.	Jul 2009	B2
7557360	Ward et al.	Jul 2009	B2
7557361	Ward et al.	Jul 2009	B2
7560715	Pedroni	Jul 2009	B2
7560717	Matsuda et al.	Jul 2009	B2
7567694	Lu et al.	Jul 2009	B2
7574251	Lu et al.	Aug 2009	B2
7576499	Caporaso et al.	Aug 2009	B2
7579603	Birgy et al.	Aug 2009	B2
7579610	Grozinger et al.	Aug 2009	B2
7582866	Furuhashi et al.	Sep 2009	B2
7582885	Katagiri et al.	Sep 2009	B2
7586112	Chiba et al.	Sep 2009	B2
7598497	Yamamoto et al.	Oct 2009	B2
7609009	Tanaka et al.	Oct 2009	B2
7609809	Kapatoes et al.	Oct 2009	B2
7609811	Siljamaki et al.	Oct 2009	B1
7615942	Sanders et al.	Nov 2009	B2
7626347	Sliski et al.	Dec 2009	B2
7629598	Harada	Dec 2009	B2
7639853	Olivera et al.	Dec 2009	B2
7639854	Schnarr et al.	Dec 2009	B2
7643661	Ruchala et al.	Jan 2010	B2
7656258	Antaya	Feb 2010	B1
7659521	Pedroni	Feb 2010	B2
7659528	Uematsu	Feb 2010	B2
7668291	Nord et al.	Feb 2010	B2
7672429	Urano et al.	Mar 2010	B2
7679073	Urano et al.	Mar 2010	B2
7682078	Rietzel	Mar 2010	B2
7692166	Muraki et al.	Apr 2010	B2
7692168	Moriyama et al.	Apr 2010	B2
7696499	Miller et al.	Apr 2010	B2
7696847	Antaya	Apr 2010	B2
7701677	Schultz et al.	Apr 2010	B2
7709818	Matsuda et al.	May 2010	B2
7710051	Caporaso et al.	May 2010	B2
7718982	Sliski et al.	May 2010	B2
7728311	Gall	Jun 2010	B2
7746978	Cheng et al.	Jun 2010	B2
7755305	Umezawa et al.	Jul 2010	B2
7759642	Nir	Jul 2010	B2
7763867	Birgy et al.	Jul 2010	B2
7767988	Kaiser et al.	Aug 2010	B2
7770231	Prater et al.	Aug 2010	B2
7772577	Saito et al.	Aug 2010	B2
7773723	Nord et al.	Aug 2010	B2
7773788	Lu et al.	Aug 2010	B2
7778488	Nord et al.	Aug 2010	B2
7783010	Clayton	Aug 2010	B2
7784127	Kuro et al.	Aug 2010	B2
7786451	Ward et al.	Aug 2010	B2
7786452	Ward et al.	Aug 2010	B2
7789560	Moyers	Sep 2010	B2
7791051	Beloussov et al.	Sep 2010	B2
7796731	Nord et al.	Sep 2010	B2
7801269	Cravens et al.	Sep 2010	B2
7801270	Nord et al.	Sep 2010	B2
7801988	Baumann et al.	Sep 2010	B2
7807982	Nishiuchi et al.	Oct 2010	B2
7809107	Nord et al.	Oct 2010	B2
7812319	Diehl et al.	Oct 2010	B2
7812326	Grozinger et al.	Oct 2010	B2
7816657	Hansmann et al.	Oct 2010	B2
7817778	Nord et al.	Oct 2010	B2
7817836	Chao et al.	Oct 2010	B2
7834334	Grozinger et al.	Nov 2010	B2
7834336	Boeh et al.	Nov 2010	B2
7835494	Nord et al.	Nov 2010	B2
7835502	Spence et al.	Nov 2010	B2
7839972	Ruchala et al.	Nov 2010	B2
7839973	Nord et al.	Nov 2010	B2
7848488	Mansfield	Dec 2010	B2
7857756	Warren et al.	Dec 2010	B2
7860216	Jongen et al.	Dec 2010	B2
7860550	Saracen et al.	Dec 2010	B2
7868301	Diehl	Jan 2011	B2
7875801	Tsotsis	Jan 2011	B2
7875861	Huttenberger et al.	Jan 2011	B2
7875868	Moriyama et al.	Jan 2011	B2
7881431	Aoi et al.	Feb 2011	B2
7894574	Nord et al.	Feb 2011	B1
7906769	Blasche et al.	Mar 2011	B2
7914734	Livingston	Mar 2011	B2
7919765	Timmer	Apr 2011	B2
7920040	Antaya et al.	Apr 2011	B2
7920675	Lomax et al.	Apr 2011	B2
7928415	Bert et al.	Apr 2011	B2
7934869	Ivanov et al.	May 2011	B2
7940881	Jongen et al.	May 2011	B2
7943913	Balakin	May 2011	B2
7947969	Pu	May 2011	B2
7949096	Cheng et al.	May 2011	B2
7950587	Henson et al.	May 2011	B2
7960710	Kruip et al.	Jun 2011	B2
7961844	Takeda et al.	Jun 2011	B2
7977648	Westerly et al.	Jul 2011	B2
7977656	Fujimaki et al.	Jul 2011	B2
7982198	Nishiuchi et al.	Jul 2011	B2
7982416	Tanaka et al.	Jul 2011	B2
7984715	Moyers	Jul 2011	B2
7986768	Nord et al.	Jul 2011	B2
7987053	Schaffner	Jul 2011	B2
7989785	Emhofer et al.	Aug 2011	B2
7990524	Jureller et al.	Aug 2011	B2
7997553	Sloan et al.	Aug 2011	B2
8002466	Von Neubeck et al.	Aug 2011	B2
8003964	Stark et al.	Aug 2011	B2
8009803	Nord et al.	Aug 2011	B2
8009804	Siljamaki et al.	Aug 2011	B2
8039822	Rietzel	Oct 2011	B2
8041006	Boyden et al.	Oct 2011	B2
8044364	Yamamoto	Oct 2011	B2
8049187	Tachikawa	Nov 2011	B2
8053508	Korkut et al.	Nov 2011	B2
8053739	Rietzel	Nov 2011	B2
8053745	Moore	Nov 2011	B2
8053746	Timmer et al.	Nov 2011	B2
8067748	Balakin	Nov 2011	B2
8069675	Radovinsky et al.	Dec 2011	B2
8071966	Kaiser et al.	Dec 2011	B2
8080801	Safai	Dec 2011	B2
8085899	Nord et al.	Dec 2011	B2
8089054	Balakin	Jan 2012	B2
8093564	Balakin	Jan 2012	B2
8093568	Mackie et al.	Jan 2012	B2
8111125	Antaya	Feb 2012	B2
8129699	Balakin	Mar 2012	B2
8144832	Balakin	Mar 2012	B2
8153989	Tachikawa et al.	Apr 2012	B2
8173981	Trbojevic	May 2012	B2
8188688	Balakin	May 2012	B2
8198607	Balakin	Jun 2012	B2
8222613	Tajiri et al.	Jul 2012	B2
8227768	Smick et al.	Jul 2012	B2
8232536	Harada	Jul 2012	B2
8278634	Vanderberg et al.	Oct 2012	B2
8288742	Balakin	Oct 2012	B2
8291717	Radovinsky et al.	Oct 2012	B2
8294127	Tachibana	Oct 2012	B2
8304725	Komuro et al.	Nov 2012	B2
8304750	Preikszas et al.	Nov 2012	B2
8309941	Balakin	Nov 2012	B2
8330132	Guertin et al.	Dec 2012	B2
8334520	Otaka et al.	Dec 2012	B2
8335397	Takane et al.	Dec 2012	B2
8344340	Gall et al.	Jan 2013	B2
8350214	Otaki et al.	Jan 2013	B2
8368038	Balakin	Feb 2013	B2
8368043	Havelange et al.	Feb 2013	B2
8373143	Balakin	Feb 2013	B2
8373145	Balakin	Feb 2013	B2
8378299	Frosien	Feb 2013	B2
8378321	Balakin	Feb 2013	B2
8382943	Clark	Feb 2013	B2
8389949	Harada et al.	Mar 2013	B2
8399866	Balakin	Mar 2013	B2
8405042	Honda et al.	Mar 2013	B2
8405056	Amaldi et al.	Mar 2013	B2
8415643	Balakin	Apr 2013	B2
8416918	Nord et al.	Apr 2013	B2
8421041	Balakin	Apr 2013	B2
8426833	Trbojevic	Apr 2013	B2
8436323	Iseki et al.	May 2013	B2
8440987	Stephani et al.	May 2013	B2
8445872	Behrens et al.	May 2013	B2
8466441	Iwata et al.	Jun 2013	B2
8472583	Star-Lack et al.	Jun 2013	B2
8483357	Siljamaki et al.	Jul 2013	B2
8487278	Balakin	Jul 2013	B2
8502173	Vanderberg et al.	Aug 2013	B2
8552406	Phaneuf et al.	Oct 2013	B2
8552408	Hanawa et al.	Oct 2013	B2
8569717	Balakin	Oct 2013	B2
8581125	Chen	Nov 2013	B2
8581215	Balakin	Nov 2013	B2
8581523	Gall et al.	Nov 2013	B2
8581525	Antaya et al.	Nov 2013	B2
8643314	Touchi	Feb 2014	B2
8653314	Pelati et al.	Feb 2014	B2
8653473	Yajima	Feb 2014	B2
8791656	Zwart	Jul 2014	B1
8927950	Gall	Jan 2015	B2
8975836	Bromberg et al.	Mar 2015	B2
9155186	Zwart	Oct 2015	B2
9185789	Zwart et al.	Nov 2015	B2
9301384	Zwart	Mar 2016	B2
9622335	Gall	Apr 2017	B2
9925395	Gall	Mar 2018	B2
20020172317	Maksimchuk et al.	Nov 2002	A1
20030048080	Amemiya et al.	Mar 2003	A1
20030125622	Schweikard et al.	Jul 2003	A1
20030136924	Kraft et al.	Jul 2003	A1
20030152197	Moyers	Aug 2003	A1
20030163015	Yanagisawa et al.	Aug 2003	A1
20030183779	Norimine et al.	Oct 2003	A1
20030234369	Glukhoy	Dec 2003	A1
20040000650	Yanagisawa et al.	Jan 2004	A1
20040017888	Seppi et al.	Jan 2004	A1
20040056212	Yanagisawa et al.	Mar 2004	A1
20040061077	Muramatsu et al.	Apr 2004	A1
20040061078	Muramatsu et al.	Apr 2004	A1
20040085023	Chistyakov	May 2004	A1
20040098445	Baumann et al.	May 2004	A1
20040111134	Muramatsu et al.	Jun 2004	A1
20040118081	Reimoser et al.	Jun 2004	A1
20040149934	Yanagisawa et al.	Aug 2004	A1
20040159795	Kaercher et al.	Aug 2004	A1
20040173763	Moriyama et al.	Sep 2004	A1
20040174958	Moriyama et al.	Sep 2004	A1
20040183033	Moriyama et al.	Sep 2004	A1
20040183035	Yanagisawa et al.	Sep 2004	A1
20040200982	Moriyama et al.	Oct 2004	A1
20040200983	Fujimaki et al.	Oct 2004	A1
20040213381	Harada	Oct 2004	A1
20040227104	Matsuda et al.	Nov 2004	A1
20040232356	Norimine et al.	Nov 2004	A1
20040240626	Moyers	Dec 2004	A1
20050058245	Ein-Gal	Mar 2005	A1
20050089141	Brown	Apr 2005	A1
20050161618	Pedroni	Jul 2005	A1
20050184686	Caporaso et al.	Aug 2005	A1
20050228255	Saracen et al.	Oct 2005	A1
20050234327	Saracen et al.	Oct 2005	A1
20050247890	Norimine et al.	Nov 2005	A1
20060017015	Sliski et al.	Jan 2006	A1
20060067468	Rietzel	Mar 2006	A1
20060126792	Li	Jun 2006	A1
20060145088	Ma	Jul 2006	A1
20060175991	Fujisawa	Aug 2006	A1
20060284562	Hruby et al.	Dec 2006	A1
20070001128	Sliski	Jan 2007	A1
20070013273	Albert et al.	Jan 2007	A1
20070014654	Haverfield et al.	Jan 2007	A1
20070023699	Yamashita et al.	Feb 2007	A1
20070029510	Hermann et al.	Feb 2007	A1
20070051904	Kaiser et al.	Mar 2007	A1
20070092812	Caporaso et al.	Apr 2007	A1
20070114945	Mattaboni et al.	May 2007	A1
20070145916	Caporaso et al.	Jun 2007	A1
20070171015	Antaya	Jul 2007	A1
20070181519	Khoshnevis	Aug 2007	A1
20070228304	Nishiuchi et al.	Oct 2007	A1
20070284548	Kaiser et al.	Dec 2007	A1
20080093567	Gall	Apr 2008	A1
20080218102	Sliski et al.	Sep 2008	A1
20090096179	Stark et al.	Apr 2009	A1
20090140671	O'Neal, III et al.	Jun 2009	A1
20090140672	Gall	Jun 2009	A1
20090200483	Gall et al.	Aug 2009	A1
20100045213	Sliski et al.	Feb 2010	A1
20100230617	Gall	Sep 2010	A1
20100308235	Sliski et al.	Dec 2010	A1
20110299919	Stark et al.	Dec 2011	A1
20120126140	Gall	May 2012	A1
20120142538	Antaya	Jun 2012	A1
20120217903	Tanaka et al.	Aug 2012	A1
20130009571	Antaya	Jan 2013	A1
20130053616	Gall et al.	Feb 2013	A1
20130127375	Sliski et al.	May 2013	A1
20131314245	Sliski et al.	May 2013
20130237425	Leigh et al.	Sep 2013	A1
20130249443	Antaya et al.	Sep 2013	A1
20140028220	Bromberg et al.	Jan 2014	A1
20140042934	Tsutsui	Feb 2014	A1
20140091734	Gall	Apr 2014	A1
20140094371	Zwart	Apr 2014	A1
20140094637	Zwart	Apr 2014	A1
20140094638	Gall et al.	Apr 2014	A1
20140094639	Zwart	Apr 2014	A1
20140094640	Gall	Apr 2014	A1
20140094641	Gall et al.	Apr 2014	A1
20140094643	Gall et al.	Apr 2014	A1
20140097920	Goldie et al.	Apr 2014	A1
20140320006	Abs et al.	Oct 2014	A1
20140371511	Zwart	Dec 2014	A1
20150090894	Zwart et al.	Apr 2015	A1

Foreign Referenced Citations (191)

Number	Date	Country
2354071	Jun 2000	CA
2629333	May 2007	CA
1377521	Oct 2002	CN
1537657	Oct 2004	CN
1816243	Aug 2006	CN
101061759	Oct 2007	CN
101361156	Feb 2009	CN
101631419	Jan 2010	CN
101932361	Dec 2010	CN
101933405	Dec 2010	CN
101933406	Dec 2010	CN
102036461	Apr 2011	CN
104244562	Dec 2014	CN
104812444	Jul 2015	CN
104813747	Jul 2015	CN
104813750	Jul 2015	CN
2753397	Jun 1978	DE
3148100	Jun 1983	DE
3530446	Mar 1986	DE
4101094	May 1992	DE
4411171	Oct 1995	DE
0194728	Sep 1986	EP
0208163	Jan 1987	EP
0221987	May 1987	EP
0222786	May 1987	EP
0276123	Jul 1988	EP
0277521	Aug 1988	EP
0306966	Mar 1989	EP
0388123	Sep 1990	EP
0465597	Jan 1992	EP
0499253	Aug 1992	EP
0776595	Jun 1997	EP
0864337	Sep 1998	EP
0911064	Apr 1999	EP
1069809	Jan 2001	EP
1153398	Nov 2001	EP
1294445	Mar 2003	EP
1348465	Oct 2003	EP
1358908	Nov 2003	EP
1371390	Dec 2003	EP
1402923	Mar 2004	EP
1430932	Jun 2004	EP
1454653	Sep 2004	EP
1454654	Sep 2004	EP
1454655	Sep 2004	EP
1454656	Sep 2004	EP
1454657	Sep 2004	EP
1477206	Nov 2004	EP
1605742	Dec 2005	EP
1738798	Jan 2007	EP
1826778	Aug 2007	EP
1949404	Jul 2008	EP
2183753	May 2010	EP
2227295	Sep 2010	EP
2232961	Sep 2010	EP
2232962	Sep 2010	EP
2363170	Sep 2011	EP
2363171	Sep 2011	EP
2394498	Dec 2011	EP
2814304	Dec 2014	EP
2900325	Aug 2015	EP
2901820	Aug 2015	EP
2901821	Aug 2015	EP
2901824	Aug 2015	EP
2560421	Aug 1985	FR
2911843	Aug 2008	FR
0957342	May 1964	GB
1360085	Jul 1974	GB
1485329	Sep 1977	GB
2015821	Sep 1979	GB
1583400	Jan 1981	GB
2361523	Oct 2001	GB
S47-028762	Dec 1972	JP
S61-225798	Dec 1973	JP
U48-108098	Dec 1973	JP
S53-77999	Jul 1978	JP
57-162527	Oct 1982	JP
S58-141000	Aug 1983	JP
S61-225798	Oct 1986	JP
62-150804	Jul 1987	JP
62-186500	Aug 1987	JP
63-149344	Jun 1988	JP
63-218200	Sep 1988	JP
63-226899	Sep 1988	JP
64-89621	Apr 1989	JP
01-276797	Nov 1989	JP
01-302700	Dec 1989	JP
4-94198	Mar 1992	JP
05-341352	Dec 1993	JP
06-036893	Feb 1994	JP
06-233831	Aug 1994	JP
07-260939	Oct 1995	JP
07-263196	Oct 1995	JP
08-173890	Jul 1996	JP
08-264298	Oct 1996	JP
09-162585	Jun 1997	JP
10-071213	Mar 1998	JP
11-47287	Feb 1999	JP
11-102800	Apr 1999	JP
11-243295	Sep 1999	JP
03-020700	Mar 2000	JP
2000-106300	Apr 2000	JP
2000-243309	Sep 2000	JP
2000-294399	Oct 2000	JP
2001-006900	Jan 2001	JP
2001-009050	Jan 2001	JP
2001-129103	May 2001	JP
2001-346893	Dec 2001	JP
2002-164686	Jun 2002	JP
2002-533888	Oct 2002	JP
2003-504628	Feb 2003	JP
2003-517755	May 2003	JP
2004-031115	Jan 2004	JP
2005-216682	Aug 2005	JP
2005-526578	Sep 2005	JP
2006-032282	Feb 2006	JP
2006-036895	Feb 2006	JP
2007-260193	Oct 2007	JP
2007-263200	Oct 2007	JP
2008-507826	Mar 2008	JP
04-128717	Jul 2008	JP
04-129768	Aug 2008	JP
04-242196	Mar 2009	JP
2009-515671	Apr 2009	JP
2009-516905	Apr 2009	JP
04-269700	May 2009	JP
04-273409	Jun 2009	JP
2009-524201	Jun 2009	JP
04-337300	Sep 2009	JP
43-23267	Sep 2009	JP
2010-536130	Nov 2010	JP
2011-501391	Jan 2011	JP
2011-505191	Feb 2011	JP
2011-505670	Feb 2011	JP
2011-507151	Mar 2011	JP
05-046928	Oct 2012	JP
2012-195279	Oct 2012	JP
300137	Nov 1969	SU
569635	Aug 1977	SU
200810614	Feb 2008	TW
200810615	Feb 2008	TW
200930160	Jul 2009	TW
200934682	Aug 2009	TW
200939908	Sep 2009	TW
200940120	Oct 2009	TW
201422279	Jun 2014	TW
201424466	Jun 2014	TW
201429514	Aug 2014	TW
201433331	Sep 2014	TW
201434508	Sep 2014	TW
WO-198607229	Dec 1986	WO
WO-1990012413	Oct 1990	WO
WO-199203028	Feb 1992	WO
WO-199302536	Feb 1993	WO
WO-199817342	Apr 1998	WO
WO-199939385	Aug 1999	WO
WO-0019786	Apr 2000	WO
WO-200040064	Jul 2000	WO
WO-200049624	Aug 2000	WO
WO-01126569	Apr 2001	WO
WO-2001026230	Apr 2001	WO
WO-0207817	Jan 2002	WO
WO-2003039212	May 2003	WO
WO-2003092812	Nov 2003	WO
WO-2004026401	Apr 2004	WO
WO-2004101070	Nov 2004	WO
WO-2006-012467	Feb 2006	WO
WO-2007061937	May 2007	WO
WO-2007084701	Jul 2007	WO
WO-2007130164	Nov 2007	WO
WO-2007145906	Dec 2007	WO
WO-2008030911	Mar 2008	WO
WO-2008081480	Jul 2008	WO
WO-2009048745	Apr 2009	WO
WO-2009070173	Jun 2009	WO
WO-2009070588	Jun 2009	WO
WO-2009073480	Jun 2009	WO
WO-200980080	Jul 2009	WO
WO-2010089574	Aug 2010	WO
WO-2010089574	Aug 2010	WO
WO-2013079311	Jun 2013	WO
WO-2013098089	Jul 2013	WO
WO-2013142409	Sep 2013	WO
WO-201405216	Jan 2014	WO
WO-2014018706	Jan 2014	WO
WO-2014018876	Jan 2014	WO
WO-2014052708	Apr 2014	WO
WO-2014052716	Apr 2014	WO
WO-2014052718	Apr 2014	WO
WO-201452719	Apr 2014	WO
WO-2014052722	Apr 2014	WO

Non-Patent Literature Citations (305)

Entry
US 8,581,524 B2, 11/2013, O'Neil et al. (withdrawn)
Office Action for TW102135161 (Chinese translation), 6 pages (dated Jul. 19, 2017).
Office Action for TW102135161 (English translation), 4 pages (dated Jul. 19, 2017).
First Office Action for JP2017-087070 (English translation), 5 pages (dated Jan. 5, 2018).
First Office Action for JP2017-087070 (Japanese translation), 6 pages (dated Jan. 5, 2018).
Notification of Grant Patent Right for CN201380062113.8, 6 pages (dated Dec. 29, 2017).
Office Action for TW102135161 (Chinese translation), 6 pages (dated Jan. 17, 2018).
Office Action for TW102135161 (English translation), 4 pages (dated Jan. 17, 2018).
Wu, Xiao Yu, “Conceptual Design and Orbit Dynamics in a 250 MeV Superconducting Synchrocyclotron”, Michigan State University, 1990 (170 pages).
18th Japan Conference on Radiation and Radioisotopes [Japanese], Nov. 25-27, 1987, 9 pages.
510(k) Summary: Ion Beam Applications S.A., FDA, Jul. 12, 2001, 5 pages.
510(k) Summary: Optivus Proton Beam Therapy System, Jul. 21, 2000, 5 pages.
Abrosimov et al., 1000MeV Proton Beam Therapy facility at Petersburg Nuclear Physics Institute Synchrocyclotron, Medical Radiology (Moscow) 32, 10 (1987) revised in Journal of Physics, Conference Series 41, 2006, pp. 424-432, Institute of Physics Publishing Limited.
Abrosimov et al., Neutron Time-of-flight Spectrometer Gneis at the Gatchina 1 GeV Protron Syncrhocyclotron, Mar. 9, 1985 and revised form Jul. 31, 1985, Lemingrad Nuclear Physics Institute, Gatchina, 188350, USSR (15 pages).
Adachi et al., A 150MeV FFAG Synchrotron with Return-Yoke Free Magent, Proceedings of the 2001 Particle Accelerator Conference, Chicago, 2001, 3 pages.
Ageyev et al., The IHEP Accelerating and Storage Complex (UNK) Status Report, 11th International Conference on High-Energy Accelerators, 1980, pp. 60-70.
Agosteo et al., Maze Design of a gantry room for proton therapy, Nuclear Instruments & Methods in Physics Research, 1996, Section A, 382, pp. 573-582.
Alexeev et al., R4 Design of Superconducting Magents for Proton Synchrotrons, Proceedings of the Fifth International Cryogenic Engineering Conference, 197 4, pp. 531-533.
Allardyce et al., Performance and Prospects of the Reconstructed CERN 600 MeV Synchrocyclotron, IEEE Transactions on Nuclear Science USA, Jun. 1977, ns-24:(3) 1631-1633.
Alonso, Magnetically Scanned Ion Beams for Radiation Therapy, Accelerator & Fusion Research Division, Lawrence Berkeley Laboratory, Berkeley, CA, Oct. 1988, 13 pages.
Amaldi et al., The Italian project for a hadrontherapy centre Nuclear Instruments and Methods in Physics Research A, 1995, 360, pp. 297-301.
Amaldi, Overview of the world landscape of Hadrontherapy and the projects of the TERA foundation, Physica Medica, An International journal Devoted to the Applications of Physics to Medicine and Biology, Jul. 1998, vol. XIV, Supplement 1, 6th Workshop on Heavy Charged Particles in Biology and Medicine, Instituto Scientific Europeo (ISE), Sep. 29-Oct. 1, 1977, Baveno, pp. 76-85.
An Accelerated Collaboration Meets with Beaming Success, Lawrence Livermore National Laboratory, Apr. 12, 2006, S&TR, Livermore, California, pp. 1-3, http://www.llnl.gov/str/April06/Caporaso.html.
Anferov et al., Status of the Midwest Proton Radiotherapy Institute, Proceedings of the 2003 Particle Accelerator Conference, 2003, pp. 699-701.
Anferov et al., The Indiana University Midwest Proton Radiation Institute, Proceedings of the 2001 Particle Accelerator Conference, 2001, Chicago, pp. 645-647.
Appun, Various problems of magnet fabrication for high-energy accelerators, Journal for All Engineers Interested in the Nuclear Field, 1967, 11 pages 10-16 (1967) [Lang.: German], English bibliogaphic information (httn://www.osti.1mv/enernvcitations/nroduct.biblio.isn?ostiid=4442292).
Arduini et al. Physical specifications of clinical proton beams from a synchrotron, Med. Phys, Jun. 1996, 23 ( 6): 939-951.
Badano et al., Proton-Ion Medical Machine Study (PIMMS) Part I, PIMMS, Jan. 1999, 238 pages.
Beam Delivery and Properties, Journal of the ICRU, 2007, 7(2):20 pages.
Beeckman et al., Preliminary design of a reduced cost proton therapy facility using a compact, high field isochronous cyclotron, Nuclear Instruments and Methods in Physics Research B56/57, 1991, pp. 1201-1204.
Bellomo et al., The Superconducting Cyclotron Program at Michigan State University, Bulletin of the American Physical Society, Sep. 1980, 25(7):767.
Benedikt and Carli, Matching to Gantries for Medical Synchrotrons IEEE Proceedings of the 1997 Particle Accelerator Conference, 1997, pp. 13 79-13 81.
Bieth et al., A Very Compact Protontherapy Facility Based on an Extensive Use of High Temperature Superconductors (HTS) Cyclotrons and their Applications 1998, Proceedings of the Fifteenth International Conference on Cyclotrons and their Applications, Caen, Jun. 14-19, 1998, pp. 669-672.
Bigham, Magnetic Trim Rods for Superconducting Cyclotrons, Nuclear Instruments and Methods (North-Holland Publishing Co.), 1975, 141:223-228.
Bimbot, First Studies of the External Beam from the Orsay S.C. 200 MeV, Institut de Physique Nucleaire, BP 1, Orsay, France, IEEE, 1979, pp. 1923-1926.
Blackmore et al., Operation of the Triumf Proton Therapy Facility, IEEE Proceedings of the 1997 Particle Accelerator Conference, May 12-16, 19973:3831-3833.
Bloch, The Midwest Proton Therapy Center, Application of Accelerators in Research and Industry, Proceedings of the Fourteenth Int'l. Conf, Part Two, Nov. 1996, pp. 1253-1255.
Blosser et al., A Compact Superconducting Cyclotron for the Production of High Intensity Protons, Proceedings of the 1997 Particle Accelerator Conference, May 12-16, 1997, 1:1054-1056.
Blosser et al., Advances in Superconducting Cyclotrons at Michigan State University, Proceedings of the 11th International Conference on Cyclotrons and their Applications, Oct. 1986, pp. 157-167, Tokyo.
Blosser et al., Characteristics of a 400 (Q2/A) MeV Super-Conducting Heavy-Ion Cyclotron, Bulletin of the American Physical Society, Oct. 1974, p. 1026.
Blosser et al., Medical Accelerator Projects at Michigan State Univ. IEEE Proceedings of the 1989 Particle Accelerator Conference, Mar. 20-23, 1989, 2:742-746.
Blosser et al., Problems and Accomplishments of Superconducting Cyclotrons, Proceedings of the 14th International Conference, Cyclotrons and Their Applications, Oct. 1995, pp. 674-684.
Blosser et al., Superconducting Cyclotron for Medical Application, IEEE Transactions on Magnetics, Mar. 1989, 25(2): 1746-1754.
Blosser et al., Superconducting Cyclotrons, Seventh International Conference on Cyclotrons and their Applications, Aug. 19-22, 1975, pp. 584-594.
Blosser, Application of Superconductivity in Cyclotron Construction, Ninth International Conference on Cyclotrons and their Applications, Sep. 1981, pp. 147-157.
Blosser, Applications of Superconducting Cyclotrons, Twelfth International Conference on Cyclotrons and Their Applications, May 8-12, 1989, pp. 137-144.
Blosser, Future Cyclotrons, AIP, The Sixth International Cyclotron Conference, 1972, pp. 16-32.
Blosser, H., Present and Future Superconducting Cyclotrons, Bulletin of the American Physical Society, Feb. 1987, 32(2):171 Particle Accelerator Conference, Washington, D.C.
Blosser, H.G., Superconducting Cyclotrons at Michigan State University, Nuclear Instruments & Methods in Physics Research, 1987,vol. B 24/25, part II, pp. 752-756.
Blosser, Medical Cyclotrons, Physics Today, Special Issue Physical Review Centenary, Oct. 1993, pp. 70-73.
Blosser, Preliminary Design Study Exploring Building Features Required for a Proton Therapy Facility for the Ontario Cancer Institute, Mar. 1991, MSUCL-760a, 53 pages.
Blosser, Progress on the Coupled Superconducting Cyclotron Project, Bulletin of the American.
Blosser, Synchrocyclotron Improvement Programs, IEEE Transactions on Nuclear Science USA, Jun. 1969, 16(3):Part I, pp. 405-414.
Blosser, The Michigan State University Superconducting Cyclotron Program, Nuclear Science, Apr. 1979, NS-26(2):2040-2047.
Botha et al., A New Multidisciplinary Separated-Sector Cyclotron Facility, IEEE Transactions on Nuclear Science, 1977, NS-24(3): 1118-1120.
Canadian Office action issued in Canadian application No. 2,629,333 dated Aug. 30, 2010, 5 pages.
Chichili et al., Fabrication ofNb3Sn Shell-Type Coils with Pre-Preg Ceramic Insulation, American Institute of Physics Conference Proceedings, AIP USA, No. 711, (XP-002436709, ISSN: 0094-243X), 2004, pp. 450-457.
Chinese Office action from corresponding Chinese application No. 200880125832.9, dated Jun. 5, 2012, 4 pages.
Chinese Office Action issued in Chinese Application No. 200780102281.X, dated Dec. 7, 2011, 23 pages (with English translation).
Chinese Office action issued in Chinese application No. 200880125832.9, dated Sep. 22, 2011, 18 pages.
Chinese Office action issued in Chinese application No. 200880125918.1, dated Sep. 15, 2011, 111 pages.
Chong et al., Radiology Clinic North American 7, 3319, 1969, 27 pages.
Chu et al., Instrumentation for Treatment of Cancer Using Proton and Light-ion Beams, Review of Scientific Instruments, Aug. 1993, 64 (8):2055-2122.
Chu et al., Performance Specifications for Proton Medical Facility, Lawrence Berkeley Laboratory, University of California, Mar. 1993, 128 pages.
Chu, “Instrumentation in Medical Systems,” Accelerator and Fusion Research Division, Lawrence Berkeley Laboratory, University of California, Berkeley, CA, May 1995, 9 pages.
Cohen, R. et al., “Nevis Synchrocyclotron Conversion Project”, IEEE Transactions on Nuclear Science, IEEE Service Center, New York, NY, US, vol. 16, No. 3, Jun. 1, 1969, pp. 421-425, XP011351570, ISSN: 0018-9499, DOI: 10.1109/TNS.1969.4325264 abstract; figures l-4a Chap. 1, p. 421-2; chap. 11 from p. 423, col. 2 top. 425, col. 1. (5 pages).
Cole et al., Design and Application of a Proton Therapy Accelerator, Fermi National Accelerator Laboratory, IEEE, 1985, 5 pages.
Collins, et al., The Indiana University Proton Therapy System, Proceedings of EPAC 2006, Edinburgh, Scotland, 2006, 3 pages.
Conradi et al., Proposed New Facilities for Proton Therapy at iThemba Labs, Proceedings of EPAC, 2002, pp. 560-562.
C/E Source of Ions for Use in Sychro-Cyclotrons Search, Jan. 31, 2005, 9 pages.
Source Search Cites of U.S. and Foreign Patents/Published applications in the name of Mitsubishi Denki Kabushiki Kaisha and Containing the Keywords (Proton and Synchrocyclotron), Jan. 2005, 8 pages.
Cosgrove et al., Microdosimetric Studies on the Orsay Proton Synchrocyclotron at 73 and 200 MeV, Radiation Protection Dosimetry, 1997, 70(1-4):493-496.
Coupland, High-field (5 T) pulsed superconducting dipole magnet, Proceedings of the Institution of Electrical Engineers, Jul. 1974, 121(7):771-778.
Coutrakon et al. Proton Synchrotrons for Cancer Therapy, Application of Accelerators in Research and Industry—Sixteenth International Conf., American Institute of Physics, Nov. 1-5, 2000, vol. 576, pp. 861-864.
Coutrakon et al., A prototype beam delivery system for the proton medical accelerator at Loma Linda, Medical Physics, Nov./Dec. 1991, 18(6):1093-1099.
CPAC Highlights Its Proton Therapy Program at ESTRO Annual Meeting, TomoTherapy Incorporated, Sep. 18, 2008, Madison, Wisconsin, pp. 1-2.
Cuttone, Applications of a Particle Accelerators in Medical Physics, Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, V.S. Sofia, 44 Cantania, Italy, Jan. 2010, 17 pages.
Dahl P, Superconducting Magnet System, American Institute of Physics, AIP Conference Proceedings, 1987-1988, 2: 1329-1376.
Dey, M.K., et al., “Coil Centering for the Kolkata Superconducting Cyclotron Magnet”, Cyclotrons and their applications, Proceedings, 18th International Conference, Cyclotrons 2007, Giardini Naxo, Italy, Oct. 1-5, 2007 (3 pages).
Dialog Search, Jan. 31, 2005, 18 pages.
Dugan et al., Tevatron Status IEEE, Particle Accelerator Conference, Accelerator Science & Technology, 1989, pp. 426-430.
Eickhoff et al., The Proposed Accelerator Facility for Light Ion Cancer Therapy in Heidelberg, Proceedings of the 1999 Particle Accelerator Conference, New York, 1999, pp. 2513-2515.
Elo, Don, et al., “Mechanical Design of Regenerative Deflector for the Berkeley 88-Inch Cyclotron”, Proceedings of the International Conference on Isochronous Cyclotrons, Gatlinburg, Tennessee, Aug. 1966 (7 pages).
Enchevich et al., Minimizing Phase Losses in the 680 MeV Synchrocyclotron by Correcting the Accelerating Voltage Amplitude, Atomnava EnerRiva, 1969, 26:(3):315-316.
Endo et al., Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy, Proceedings of EPAC 2002, Paris France, 2002, pp. 2733-2735.
European Communication issued in corresponding European application No. 11165423.4, dated Sep. 2, 2011, 5 pages.
European communication issued in European application 13774340.7 dated May 20, 2015 (2 pages).
European Communication issued in European application No. 07868958.5, dated Nov. 26, 2010, 50 pages.
European Patent Office communication issued in European application No. 08856764.9, dated Jul. 30, 2010, 2 pages.
European Patent Office communication issued in European application No. 07868958.5, dated Jul. 16, 2010, 2 pages.
European Search Report from European Application No. 14170555.8 dated Oct. 15, 2014 (4 pages).
European Search Report from European Application No. 141717 07.4 dated Nov. 28, 2014 (6 pages).
European Search Report from European Application No. 14171707.4 dated Nov. 4, 2014 (3 pages).
European Search Report issued in European Application No. 11165423.2, dated Aug. 8, 2011, 118 pages.
First Office Action of CN20141040457 4.5, 11 pages (dated Mar. 1, 2016).
Flanz et al., Large Medical Gantries, Particle Accelerator Conference, Massachusetts General Hospital, 1995, pp. 1-5.
Flanz et al., Operation of a Cyclotron Based Proton Therapy Facility, Massachusetts General Hospital, Boston, MA 02114, pp. 1-4, retrieved from Internet in 2009.
Flanz et al., The Northeast Proton Therapy Center at Massachusetts General Hospital, Fifth Workshop on Heavy Charge Particles in Biology and Medicine, GSI, Darmstadt, Aug. 1995, 11 pages.
Flanz et al., Treating Patients with the NPTC Accelerator Based Proton Treatment Facility, Proceedings of the 2003 Particle Accelerator Conference, 2003, pp. 690-693.
Flood and Frazier, The Wide-Band Driven RF System for the Berkeley 88-Inch Cyclotron, American Institute of Physics, Conference Proceedings., No. 9, 1972, 459-466.
Foster and Kashikhin, Superconducting Superferric Dipole Magent with Cold Iron Core for the VLHC, IEEE Transactions on Applied Superconductivity, Mar. 2002, 12(1):111-115.
Friesel et al., Design and Construction Progress on the IUCF Midwest Proton Radiation Institute, Proceedings of EPAC 2002, 2002, pp. 2736-2738.
Fukumoto et al., A Proton Therapy Facility Plan Cyclotrons and their Applications, Proceedings of the 13th International Conference, Vancouver, Canada, Jul. 6-10, 1992, pp. 258-261.
Fukumoto, Cyclotron Versus Synchrotron for Proton Beam Therapy, KEK Prepr., No. 95-122, Oct. 1995, pp. 533-536.
Goto et al., Progress on the Sector Magnets for the Riken SRC, American Institute of Physics, 714 CP600, Cyclotrons and Their Applications 2001, Sixteenth International Conference, 2001, pp. 319-323.
Graffman et al., Acta Radial. Therapy Phys. Biol. 1970, 9, 1 (1970).
Graffman et al., Design Studies for a 200 MeV Proton Clinic for Radiotherapy, AIP Conference Proceedings: Cyclotrons—1972, 1972, No. 9, pp. 603-615.
Graffman, et. al. Proton radiotherapy with the Uppsala cyclotron. Experience and plans Strahlentherapie, 1985, 161(12):764-770.
Hede, Research Groups Promoting Proton Therapy Lite, Journal of the National Cancer Institute, Dec. 6, 2006, 98(23):1682-1684.
Heinz, Superconducting Pulsed Magnetic Systems for High-Energy Synchrotrons, Proceedings of the Fourth International Cryogenic Engineering Conference, May 24-26, 1972, pp. 55-63.
Hentschel et al., Plans for the German National Neutron Therapy Centre with a Hospital-Based 70 MeV Proton Cyclotron at University Hospital Essen/Germany, Cyclotrons and their Applications, Proceedings of the Fifteenth International Conference on Cyclotrons and their Applications, Caen, Franco, Jun. 14-19, 1998, pp. 21-23.
Hepburn et al., Superconducting Cyclotron Neutron Source for Therapy, International Journal of Radiation Oncology Biology Physics, vol. 3 complete, 1977, pp. 387-391.
Hirabayashi, Development of Superconducting Magnets for Beam Lines and Accelerator at KEK, IEEE Transaction on Magnetics, Jan. 1981, Mag-17(1 ):728-731.
Indiana's mega-million proton therapy cancer center welcomes its first patients [online] Press release, Health & Medicine Week, 2004, retrieved from NewsRx.com, Mar. 1, 2004, pp. 119-120.
International Preliminary Report on Patentability in International Application No. PCT/US2006/44853, dated May 29, 2008, 8 pages.
International Preliminary Report on Patentability in International Application No. PCT/US2007/001506, dated Jul. 5, 2007, 15 pages.
International Preliminary Report on Patentability in International Application No. PCT/US2007/001628, dated Apr. 22, 2008, 20 pages.
International Preliminary Report on Patentability issued in PCT Application No. PCT/US2008/084695, dated Jun. 10, 2010, 10 pages.
International Preliminary Report on Patentability issued in PCT Application No. PCT/US2008/084699, dated Jun. 10, 2010, 8 pages.
International Preliminary Report on Patentability issued in PCT Application No. PCT/US2007/086109, dated Jun. 10, 2010, 7 pages.
International Preliminary Report on Patentability on International Application No. PCT/US2008/077513, dated Apr. 22, 2010.
International Report on Patentability issued in PCT application PCT/US2013/062117 dated Apr. 9, 2015 (11 pages).
International Search Report and Written Opinion in International Application No. PCT /US2007/086109, dated Aug. 26, 2008, 51 pages.
International Search Report and Written Opinion in International Application No. PCT/US2006/44853, dated Oct. 5, 2007, 12 pages.
International Search Report and Written Opinion in International Application No. PCT/US2007/001506, dated Jul. 5, 2007, Publication No. W02007/084701, Published Jul. 26, 2007, 14 pages.
International Search Report and Written Opinion in International Application No. PCT/US2008/077513, dated Oct. 1, 2009, 73 pages.
International Search Report and Written Opinion in International Application No. PCT/US2008/084695, dated Jan. 26, 2009, 15 pages.
International Search Report and Written Opinion in International Application No. PCT/US2008/084699, dated Feb. 4, 2009, 11 pages.
International Search Report and Written Opinion dated Apr. 17, 2014 from corresponding PCT application No. PCT/US2013/062112 (13 pages).
International Search Report and Written Opinion dated Jun. 10, 2014 from PCT application No. PCT/US2013/062102 (11 pages).
International Search Report and Written Opinion dated May 26, 2014 from corresponding PCT application No. PCT/US2013/062117 (13 pages).
International Search Report in International Application No. PCT/US2007/001628, dated Feb. 18, 2008, 4 pages.
Invitation to pay additional fees and, where applicable, protest fee dated Nov. 25, 2013 from corresponding PCT application No. PCT/US2013/062117 (5 pages) (including attached search report).
Ishibashi and Mcinturff, Stress Analysis of Superconducting 1 OT Magnets for Synchrotron, Proceedings of the Ninth International Cryogenic Engineering Conference, May 11-14, 1982, pp. 513-516.
Ishibashi and Mcinturff, Winding Design Study of Superconducting 10 T Dipoles for a Synchrotron, IEEE Transactions on Magnetics, May 1983, MAG-19(3):1364-1367.
Jahnke et al., First Superconducting Prototype Magnets for a Compact Synchrotron Radiation Source in Operation, IEEE Transactions on Magnetics, Mar. 1988, 24(2):1230-1232.
Japanese Office action with English translation in corresponding Japanese application 2014-120409 dated Jan. 18, 2016 (10 pages).
Jones and Dershem, Synchrotron Radiation from Proton in a 20 TEV, 10 TESLA Superconducting Super Collider Proceedings of the 12th International Conference on High-Energy Accelerator, Aug. 11-16, 1983, pp. 138-140.
Jones and Mills, The South African National Accelerator Centre: Particle Therapy and Isotope Production Programmes, Radiation Physics and Chemistry, Apr.- Jun. 1998, 51 ( 4-6):571-578.
Jones et al., Status Report of the NAC Particle Therapy Programme, Stralentherapie und Onkologie, vol. 175, Suppl. II, Jun. 1999, pp. 30-32.
Jones, Present Status and Future Trends of Heavy Particle Radiotherapy, Cyclotrons and their Applications 1998, Proceedings of the Fifteenth International Conference on Cyclotrons and their Applications, Jun. 14-19, 1998, pp. 13-20.
Jongen et al., Development of a Low-cost Compact Cyclotron System for Proton Therapy, National Institute of Radiol. Sci,1991, No. 81, DD. 189-200.
Jongen et al., Progress report on the IBA-SHI small cyclotron for cancer therapy Nuclear Instruments and Methods in Physics Research, Section B, vol. 79, issue 1-4, 1993, pp. 885-889.
Jongen et al., The proton therapy system for MGH's NPTC: equipment description and progress report, Bulletin du Cancer/Radiotherapie, Proceedings of the meeting of the European Heavy Particle Therapy Group, 1996, 83(Suppl. 1):219-222.
Jongen et al., The proton therapy system for the NPTC: Equipment Description and progress report, Nuclear Instruments and methods in physics research, 1996, Section B, 113(1 ): 522-525.
Kanai et al., Three-dimensional Beam Scanning for Proton Therapy, Nuclear Instruments and Methods in Physic Research, Sep. 1, 1983, The Netherlands, 214(23):491-496.
Karlin et al., Medical Radiology (Moscow), 1983, 28, 13.
Karlin et al., The State and Prospects in the Development of the Medical Proton Tract on the Synchrocyclotron in Gatchina, Med. Radial., Moscow, 28(3):28-32 (Mar. 1983)(German with English Abstract on end of p. 32).
Kats and Druzhinin, Comparison of Methods for Irradiation Prone Patients, Atomic Energy, Feb. 2003, 94(2): 120-123.
Kats and Onosovskii, A Planar Magnetooptical System for the Irradiation of a Lying Patient with a Proton Beam from Various Directions, Instruments and Experimental Techniques, 1996, 39(1):127-131.
Kats and Onosovskii, A Simple, Compact, Flat System for the Irradiation of a Lying Patient with a Proton Beam from Different Directions, Instruments and Experimental Techniques, 1996, 39(1):132-134.
Khoroshkov et al., Moscow Hospital-Based Proton Therapy Facility Design, Am. Journal Clinical Oncology: CCT, Apr. 1994, 17(2):109-114.
Kim and Blosser, Optimized Magnet for a 250 MeV Proton Radiotherapy Cyclotron, Cyclotrons and Their Applications 2001, May 2001, Sixteenth International Conference, pp. 345-347.
Kim and Yun, A Light-Ion Superconducting Cyclotron System for Multi-Disciplinary Users, Journal of the Korean Physical Society, Sep. 2003, 43(3):325-331.
Kim et al., Construction of 8T Magnet Test Stand for Cyclotron Studies, IEEE Transactions on Applied Superconductivity, Mar. 1993, 3(1):266-268.
Kim et al., Design Study of a Superconducting Cyclotron for Heavy Ion Therapy, Cyclotrons and Their Applications 2001, Sixteenth International Conference, May 13-17, 2001, pp. 324-326.
Kim et al., Trim Coil System for the Riken Cyclotron Ring Cyclotron, Proceedings of the 1997 Particle Accelerator Conference, IEEE, Dec. 1981, vol. 3, pp. 214-235 or 3422-3424, 1998.
Kim, An Eight Tesla Superconducting Magnet for Cyclotron Studies, Ph.D. Dissertation, Michigan State University, Department of Physics and Astronomy, 1994, 13 8 pages.
Kimstrand, Beam Modelling for Treatment Planning of Scanned Proton Beams, Digital Comprehensive Summaries of Uppsala dissertations from the Faculty of Medicine 330, Uppsala Universitet, 2008, 58 pages.
Kishida and Yano, Beam Transport System for the RIKEN SSC (II), Scientific Papers of the Institute of Physical and Chemical Research, Dec. 1981, 75(4):214-235.
Koehler et al., Range Modulators for Protons and Heavy Ions, Nuclear Instruments and Methods, 1975, vol. 131, pp. 437-440.
Koto and Tsujii, Future of Particle Thera12y, Ja12anese Journal of Cancer Clinics, 2001, 47(1):95-98 [Lang.: Japanese], English abstract (htt12://sciencelinks.j12/jeast/article/200206/000020020601A05 I I 453.nhn).
Kraft et al., Hadrontherapy in Oncology, U. Amaldi and Larrsson, editors Elsevier Science, 1994, 161 pages.
Krevet et al., Design of a Strongly Curved Superconducting Bending Magnet for a Compact Synchrotron Light Source, Advances in Cryogenic Engineering, 1988, vol. 33, pp. 25-32.
Kullander, S. et al., Some Studies on Regenerative Beam Extraction in Synchrocyclotrons, IEEE Transactions on Nuclear Science, pp. 106-113 (1966).
Laisne et al., The Orsay 200 MeV Synchrocyclotron, IEEE Transactions on Nuclear Science, Apr. 1979, NS-26(2):1919-1922.
Larsson et al., Nature, 1958, 182:1222.
Larsson, Biomedical Program for the Converted 200-MeV Synchrocyclotron at the Gustaf Werner Institute, Radiation Research, 1985, 104:S310-S318.
Lawrence et al., Heavy particles in acromegaly and Cushing's Disease, in Endocrine and Norendocrine Hormone Producing Tumors (Year Book Medical Chicago, 1973, pp. 29-61.
Lawrence et al., Successful Treatment of Acromegaly: Metabolic and Clinical Studies in 145 Patients, The Journal of Clinical Endrocrinology and Metabolism, Aug. 1970, 31(2), 21 pages.
Lawrence et al., Treatment of Pituitary Tumors, (Excerpta medica, Amsterdam/American Elsevier, New York, 1973, pp. 253-262.
Lawrence, Cancer, 1957, 10:795.
Lecroy et al., Viewing Probe for High Voltage Pulses, Review of Scientific Instruments USA, Dec. 1960, 31(12):1354.
Lin et al., Principles and 10 Year Experience of the Beam Monitor System at the PSI Scanned Proton Therapy Facility, Center for Proton Radiation Therapy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland, 2007, 21 pages.
Linfoot et al., Acromegaly, in Hormonal Proteins and Peptides, edited by C.H. Li, 1975, pp. 191-246.
Literature Author and Keyword Search, Feb. 14, 2005, 44 pages.
Literature Keyword Search, Jan. 24, 2005, 98 pages.
Literature Search and Keyword Search for Synchrocyclotron, Jan. 25, 2005, 68 pages.
Literature Search by Company Name/Component Source, Jan. 24, 2005, 111 pages.
Literature Search, Jan. 26, 2005, 37 pages.
Livingston et al., A capillary ion source for the cyclotron, Review Science Instruments, Feb. 1939, 10:63.
LLNL, UC Davis Team Up to Fight Cancer, Lawrence Livermore National Laboratory, Apr. 28, 2006, SF-06-04-02, Livermore, California, pp. 1-4.
Mandrillon, High Energy Medical Accelerators, EPAC 90, 2nd European Particle Accelerator Conference, Jun. 12-16, 1990, 2:54-58.
Marchand et al., IBA Proton Pencil Beam Scanning: an Innovative Solution for Cancer Treatment, Proceedings of EP AC 2000, Vienna, Austria, 3 pages.
Marti et al., High Intensity Operation of a Superconducting Cyclotron, Proceedings of the I 4the International Conference, Cyclotrons and Their Applications, Oct. 1995, pp. 45-48 (Oct. 1995).
Martin, Operational Experience with Superconducting Synchrotron Magnets Proceedings of the 1987 IEEE Particle Accelerator Conference, Mar. 16-19, 1987, vol. 3 of 3: 1379-1382.
Meote et al., ETOILE Hadrontherapy Project, Review of Design Studies Proceedings of EPAC 2002, 2002, pp. 2745-2747.
Miyamoto et al., Development of the Proton Therapy System, The Hitachi Hyoron, 79(10):775-775 779 (1997) [Lang: Japanese], English abstract (http://www.hitachi.com/rev/1998/revfeb98/rev4 706.htm).
Montelius et al., The Narrow Proton Beam Therapy Unit at the Svedberg Laboratory in Uppsala, ACTA Oncologica, 1991, 30:739-745.
Moser et al., Nonlinear Beam Optics with Real Fields in Compact Storage Rings, Nuclear Instruments & Methods in Physics Research/Section B, B30, Feb. 1988, No. 1, pp. 105-109.
Moyers et al., A Continuously Variable Thickness Scatterer for Proton Beams Using Self-compensating Dual Linear Wedges Loma Linda University Medical Center, Dept. of Radiation Medicine, Loma Linda, CA, Nov. 2, 1992, 21 pages.
National Cancer Institute Funding (Senate-Se12tember 21, I 992} (w<lvw.tbomas.loc.gov/cgibin/querv/z?rI02:S21SE2-7I2 12 na2es).
Nicholson, Applications of Proton Beam Therapy, Journal of the American Society of Radiologic Technologists, May/Jun. 1996, 67(5): 439-441.
Nolen et al., The Integrated Cryogenic-Superconducting Beam Transport System Planned for MSU, Proceedings of the J21h International Conference on High-Energy Accelerators, Aug. 1983, pp. 549-551.
Norimine et al., A Design of a Rotating Gantry with Easy Steering for Proton Therapy, Proceedings of EPAC 2002, 2002, pp. 2751-2753.
Office Action (Chinese translation) for TW102135161, 58 pages (dated Nov. 28, 2016).
Office Action (English translation) for TW102135161, 5 pages (dated Nov. 28, 2016).
Office Action for U.S. Appl. No. 14/039,652, 84 pages (dated Jul. 27, 2016).
Office Action in counterpart Chinese application No. 201380062113.8, dated Aug. 29, 2016 (Chinese language).
Office Action in counterpart Chinese application No. 201380062113.8, dated Aug. 29, 2016 (English translation).
Office Action with English translation from Japanese Application 2014-120409 dated Jun. 15, 2015 (8 pages).
Ogino, Takashi, Heavy Charged Particle Radiotherapy-Proton Beam, Division of Radiation Oncology, National Cancer Hospital East, Kashiwa, Japan, Dec. 2003, 7 pages.
Okumura et al., Overview and Future Prospect of Proton Radiotherapy, Japanese Journal of Cancer Clinics, 1997, 43(2):209-214 [Lang.: Japanese].
Okumura et al., Proton Radiotherapy Japanese Journal of Cancer and Chemotherapy, 1993, 10. 20(14):2149-2155[Lang.: Japanese].
Ormrod, J.H., et al, “Status of the Chalk-River Superconducting Heavy-Ion Cyclotron”, Proceedings of 9th International Conference on Cyclotrons and their Applications '81, 1981 (9 pages).
Ormrod, J.H., et al., “The Chalk-River Superconducting Cyclotron”, Proceedings of the International Conference on Cyclotrons and their applications '79, 1979 (6 pages).
Outstanding from Search Reports, Accelerator of Polarized Portons at Fermilab, 2005, 20 pages.
Paganetti et al., Proton Beam Radiotherapy—The State of the Art, Springer Verlag, Heidelberg, ISBN 3-540-00321-5, Oct. 2005,36 pages.
Palmer and Tollestrup, Superconducting Magnet Technology for Accelerators, Annual Review of Nuclear and Particle Science, 1984, vol. 34, pp. 247-284.
Patent Assignee and Keyword Searches for Synchrocyclotron, Jan. 25, 2005, 78 pages.
Patent Assignee Search Paul Scherrer Institute, Library Services at Fish & Richardson P.C., Mar. 20, 2007, 40 pages.
Patent Prior Art Search for ‘Proton Therapy System’, Library Services at Fish & Richardson P.C., Mar. 20, 2007, 46 pages.
Pavlovic, Beam-optics study of the gantry beam delivery system for light-ion cancer therapy, Nuclear Instruments and Methods in Physics Research, Section A, Nov. 1997, 399(2):439-454(16).
Pedroni and Enge, Beam optics design of compact gantry for proton therapy Medical & Biological Engineering & Computing, May 1995, 33(3):271-277.
Pedroni and Jermann, SGSMP: Bulletin Mar. 2002 Proscan Project, Progress Report on the PROSCAN.
Pedroni et al., A Novel Gantry for Proton Therapy at the Paul Scherrer Institute, Cycloctrons and Their Applications 2001: Sixteenth International Conference. AIP Conference Proceedings, 2001, 600:13-17.
Pedroni et al., The 200-MeV proton therapy project at the Paul Scherrer Institute: Conceptual design and practical realization, Medical Physics, Jan. 1995, 22(1 ):37-53.
Pedroni, Accelerators for Charged Particle Therapy: Performance Criteria from the User Point of View, Cyclotrons and their Applications, Proceedings of the 13th International Conference, Jul. 6-10, 1992, pp. 226-233.
Pedroni, Latest Developments in Proton Therapy Proceedings of EPAC 2000, pp. 240-244, 2000.
Pedroni, Status of Proton Therapy: results and future trends, Paul Scherrer Institute, Division of Radiation Medicine, 1994, 5 pages.
Peggs et al., A Survey of Hadron Therapy Accelerator Technologies, Particle Accelerator Conference, Jun. 25-29, 2008, 7 pages.
Potts et al., MPWP6-Therapy III: Treatment Aids and Techniques Medical Physics, Sep./Oct. 1988, 15(5):798.
Pourrahimi et al., Powder Metallurgy Processed Nb3Sn(Ta) Wire for High Field NMR magnets, IEEE Transactions on Applied Superconductivity, Jun. 1995, 5(2):1603-1606.
Prieels et al., The IBA State-of-the-Art Proton Therapy System, Performances and Recent Results, Application of Accelerators in Research and industry—Sixteenth Int'l. Conj, American Institute of Physics, Nov. 1-5, 2000, 576:857-860.
Prosecution History of U.S. Appl. No. 14/039,073 (downloaded Jul. 17, 2014).
Rabin et al., Compact Designs for Comprehensive Proton Beam Clinical Facilities, Nuclear Instruments & Methods in Physics Research, Apr. 1989, Section B, vol. 40-41, Part II, pp. 1335-1339.
Rainwater, James, “Status of the Nevis Synchrocyclotron Modification”, AIP Conference Proceedings No. 9, 1972 (14 pages).
Research & Development Magazine, Proton Therapy Center Nearing Completion, Aug. 1999, 41(9):2 pages (www.rdmag.com).
Resmini,, Design Characteristics of the K=800 Superconducting Cyclotron at M.S.U., Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, IEEE Transaction on Nuclear Science, vol. NS-26, No. 2, Apr. 1979, 8 pages.
Response to European Communication in European application 13774340.7 dated May 20, 2015 filed on Nov. 20, 2015 (25 pages).
Response to European Communication dated Nov. 28, 2014 in corresponding European Application 14171707.4, filed on Mar. 24, 2015 (29 pages).
Response with English translation to Japanese office action dated Jun. 15, 2015 in corresponding Japanese application 2014-120409, filed on Oct. 14, 2015 (23 pages).
RetroSearch Berkeley 88-Inch Cyclotron ‘RF’ or ‘Frequency Control’, Jan. 21, 2005, 36 pages.
RetroSearch Berkeley 88-Inch Cyclotron, Jan. 24, 2005, 170 pages.
RetroSearch Bernard Gottschalk, Cyclotron, Beams, Compensated Upstream Modulator, Compensated Scatter, Jan. 21, 2005, 20 pages.
RetroSearch Cyclotron with ‘RF’ or ‘Frequency Control’, Jan. 21, 2005, 49 pages.
RetroSearch Gottschalk, Bernard, Harvard Cyclotron Wheel, Jan. 21, 2005, 20 pages.
RetroSearch Loma Linda University Beam Compensation, Jan. 21, 2005, 60 pages.
RetroSearch Loma Linda University, Beam Compensation Foil Wedge, Jan. 21, 2005, 15 pages.
Revised Patent Keyword Search, Jan. 25, 2005, 88 pages.
Rifuggiato et, al., Status Report of the LNS Superconducting Cyclotron Nukleonika, 2003, 48:SI31-SI34, Supplement 2.
Rode, Tevatron Cryogenic System, Proceedings of the 12th International Conference on Highenergy Accelerators, Fermilab, Aug. 11-16, 1983, pp. 529-535.
Salzburger et al., Superconducting Synchrotron Magnets Supraleitende Synchrotronmagnete, NTiS, 155 pages (Oct. 1975).
Schillo et al,. Compact Superconducting 250 MeV Proton Cyclotron for the PSI Proscan Proton Therapy Project, Cyclotrons and Their Applications 2001, Sixteenth International Conference, 2001, pp. 37-39.
Schneider et al., Nevis Synchrocyclotron Conversion Program—RF System, IEEE Transactions on Nuclear Science USA, Jun. 1969, ns 16(3): 430-433.
Schneider et al., Superconducting Cyclotrons, IEEE Transactions on Magnetics, vol. MAG-11, No. 2, Mar. 1975, New York, pp. 443-446.
Schreuder et al., The Non-orthogonal Fixed Beam Arrangement for the Second Proton Therapy Facility at the National Accelerator Centre, Application of Accelerators in Research and Industry, American Institute of Physics, Proceedings of the Fifteenth International Conference, Nov. 1998, Part Two, pp. 963-966.
Schreuder, Recent Developments in Superconducting Cyclotrons, Proceedings of the 1995 Particle Accelerator Conference, May 1-5, 1995, vol. 1, pp. 317-321.
Schubert and Blosser, Conceptual Design of a High Field Ultra-Compact Cyclotron for Nuclear Physics Research, Proceedings of the 1997 Particle Accelerator Conference, May 12-16, 1997, vol. 1, 3 pages 1060-1062.
Schubert, Extending the Feasibility Boundary of the Isochronous Cyclotron, Dissertation submitted to Michigan State University, 1997, Abstract http://adsabs.harvard.edu/abs/1998PhDT ....... 147S.
Search Report (English translation) for TW102135161, 2 pages dated (dated Nov. 28, 2016).
Shelaev et al., Design Features of a Model Superconducting Synchrotron of JINR, Proceedings of the 12th International Conference on High-energy Accelerators, Aug. 11-16, 1983, pp. 416-418.
Shintomi et. Al, Technology and Materials for the Superconducting Super Collider (SSC) Project, [Lang.: Japanese], The Iron and Steel Institute of Japan 00211575, 78(8): 1305-1313, 1992, http://ci.nii.ac.ip/naid/I I 0001493249/en/.
Sisterson, Clinical use of proton and ion beams from a world-wide perspective, Nuclear Instruments and Methods in Physics Research, Section B, 1989, 40-41:1350-1353.
Sisterson, World Wide Proton Therapy Experience in 1997, The American Institute of Physics, Applications of Accelerators in Research and Industry, Proceedings of the Fifteenth International Conference, Part Two, Nov. 1998, pp. 959-962.
Slater et al., Developing a Clinical Proton Accelerator Facility: Consortium-Assisted Technology Transfer, Conference Record of the 1991 IEEE Particle Accelerator Conference: Accelerator Science and Technology, vol. I, May 6-9, 1991, pp. 532-536.
Slater et al., Development of a Hospital-Based Proton Beam Treatment Center, International Journal of Radiation Oncology Biol. J Physics, Apr. 1988, 14(4):761-775.
Smith et al., The Northeast Proton Therapy Center at Massachusetts General Hospital Journal of Brachytherapy International, Jan. 1997, pp. 137-139.
Snyder and Marti, Central region design studies for a proposed 250 MeV proton cyclotron, Nuclear Instruments and Methods in Physics Research, Section A, 1995, vol. 355, pp. 618-623.
Soga, Progress of Particle Therapy in Japan, Application of Accelerators in Research and Industry, American Institute of Physics, Sixteenth International Conference, Nov. 2000, pp. 869-872.
Spiller et al., The GSI Synchrotron Facility Proposal for Acceleration of High Intensity Ion and Proton Beams Proceedings of the 2003 Particle Accelerator Conference, May 12-16, 2003, vol. 1, pp. 589-591.
Stanford et al., Method of Temperature Control in Microwave Ferroelectric Measurements, Sperry Microwave Electronics Company, Clearwater, Florida, Sep. 19, 1960, 1 page.
Superconducting Cyclotron Contract awarded by Paul Scherrer Institute (PSI), Villigen, Switzerland, http://www.accel.de/News/superconducting_ cyclotron_ contract.htm, Jan. 2009, 1 page.
Tadashi et al., Large superconducting super collider (SSC) in the planning and materials technology,78(8):1305-1313, The Iron and Steel Institute of Japan 00211575, Aug. 1992.
Takada, Conceptual Design of a Proton Rotating Gantry for Cancer Therapy, Japanese Journal of Medical Physics, 1995, 15(4):270-284.
Takayama et al., Compact Cyclotron for Proton Therapy, Proceedings of the 81h Symposium on Accelerator Science and Technology, Japan, Nov. 25-27, 1991, pp. 380-382.
Teng, The Fermilab Tevatron, Coral Gables 1981, Proceedings, Gauge Theories, Massive Neutrinos, and Proton Decay, 1981, pp. 43-62.
The Davis 76-Inch Isochronous Cyclotron, Beam On: Crocker Nuclear Laboratory, University of California, 2009, 1 page.
The Journal of Practical Pharmacy,1995, 46(1):97-103 [Japanese].
The K100 Neutron-therapy Cyclotron, National Superconducting Cyclotron Laboratory at Michigan State University (NSCL ), retrieved from: http://www.nscl.msu.edu/tech/accelerators/kl 00, Feb. 2005, 1 page.
The K250 Proton therapy Cyclotron, National Superconducting Cyclotron Laboratory at Michigan State University (NSCL), retrieved from: http://www.nscl.msu.edu/tech/accelerators/k.250.html, Feb. 2005, 2 pages.
The K250 Proton-therapy Cyclotron Photo Illustration, National Superconducting Cyclotron Laboratory at Michigan State University (NSCL), retrieved from: http://www.nscl.msu.edu/media/image/ experimental-equipment-technology /25 0 .html, Feb. 2005, 1 page.
Tilly, et al., “Development and verification of the pulsed scanned proton beam at The Svedberg 135 Laboratory in Uppsala”, Physics in Medicine and Biology, Phys. Med. Biol. 52, pp. 2741-2454, 2007.
Tobias et al., Cancer Research,1958, 18, 121 (1958).
Tom, The Use of Compact Cyclotrons for Producing Fast Neutrons for Therapy in a Rotatable Isocentric Gantry, IEEE Transaction on Nuclear Science, Apr. 1979, 26(2):2294-2298.
Toyoda, Proton Therapy System, Sumitomo Heavy Industries, Ltd., 2000, 5 pages.
Trinks et. al., The Tritron: A Superconducting Separated-Orbit Cyclotron, Nuclear Instruments and Methods in Physics Research, Section A, 1986, vol. 244, pp. 273-282.
Tsuji, The Future and Progress of Proton Beam Radiotherapy, Journal of Japanese Society for Therapeutic Radiology and Oncology, 1994, 6(2):63-76.
U.S. Appl. No. 13/830,792, filed Mar. 14, 2013, including the USPTO electronic file for U.S. Appl. No. 13/830,792.
U.S. Appl. No. 13/838,792, filed Mar. 14, 2013, including the USPTO electronic file for U.S. Appl. No. 13/830,792.
U.S. Appl. No. 13/949,450, filed Jul. 24, 2013, including the USPTO electronic file for U.S. Appl. No. 13/949,450.
U.S. Appl. No. 13/949,459, filed Jul. 24, 2013, including the USPTO electronic file for U.S. Appl. No. 13/949,459.
U.S. Appl. No. 15/161,377, filed May 23, 2016, including the USPTO electronic file for U.S. Appl. No. 15/161,377.
U.S. Appl. No. 61/676,377, filed Jul. 27, 2012, including the USPTO electronic file for U.S. Appl. No. 61/676,377.
UC Davis School of Medicine, Unlikely Partners Turn Military Defense into Cancer Offense, Current Issue Summer 2008, Sacramento, California, pp. 1-2.
Umegaki et al., Development of an Advanced Proton Beam Therapy System for Cancer Treatment Hitachi Hyoron, 2003, 85(9):605-608 [Lang.: Japanese], English abstract, http://www.hitachi.com/ICSFiles/afieldfile/2004/06/0 l/r2003 _ 04_104.pdf or http://www.hitachi.com/rev/archive/2003/2005649_12606.html (full text) [Hitachi, 52( 4), Dec. 2003].
Umezawa et al., Beam Commissioning of the new Proton Therapy System for University of Tsukuba, Proceedings of the 2001 Particle Accelerator Conference, vol. 1, Jun. 18-22, 2001, pp. 648-650.
Van Steenbergen, Superconducting Synchroton Development at BNL, Proceedings of the 8th International Conference on Hi£h-Ener5'Y Accelerators CERN 1971, 1971, pp. 196-198.
Van Steenbergen, The CMS, a Cold Magnet Synchrotron to Upgrade the Proton Energy Range of the BNL Facility, IEEE Transactions on Nuclear Science, Jun. 1971, 18(3):694-698.
Vandeplassche et al., 235 MeV Cyclotron for MGH's Northeast Proton Therapy Center (NPTC): Present Status, EPAC 96, Fifth European Partical Accelerator Conference, vol. 3, Jun. 10-14, 1996, pp. 2650-2652.
Verster, N.F., Regenerative Beam Extraction from the 150-MeV Synchrocyclotron at the Laboratoire Curie, Proceedings of Sector-Focused Cyclotrons, pp. 224-229 (1959).
Vorobiev et al., Concepts of a Compact Achromatic Proton Gantry with a Wide Scanning Field, Nuclear Instruments and Methods in Physics Research, Section A., 1998, 406(2):307-310.
Vrenken et al., A Design of a Compact Gantry for Proton Therapy with 2D-Scanning, Nuclear Instruments and Methods in Physics Research, Section A, 1999, 426(2):618-624.
Wikipedia, Cyclotron http://en.wiki11edia.org/wiki/Cyclotron (originally visited Oct. 6, 2005, revisited Jan. 28, 2009), 7 pages.
Wikipedia, Synchrotron http://en.wiki11edia.org/wiki/Synchrotron (originally visited Oct. 6, 2005, revisited Jan. 28, 2009), 7 pages.
Worldwide Patent Assignee Search, Jan. 24, 2005, 224 pages.
Worldwide Patent Keyword Search, Jan. 24, 2005, 94 pages.
Written Opinion in PCT Application No. PCT/US2007/001628, dated Feb. 18, 2008, 11 pages.
Wu, Conceptual Design and Orbit Dynamics in a 250 MeV Superconducting Synchrocyclotron, Ph.D. Dissertation, Michigan State University, Department of Physics and Astronomy, 1990, 172 pages.
York et al., Present Status and Future Possibilities at NSCL-MSU, EP AC 94, Fourth European Particle Accelerator Conference, pp. 554-556, Jun. 1994.
York et al., The NSCL Coupled Cyclotron Project—Overview and Status, Proceedings of the Fifteenth International Conference on Cyclotrons and their Applications, Jun. 1998, pp. 687-691.
Yudelev et al., Hospital Based Superconducting Cyclotron for Neutron Therapy: Medical Physics Perspective, Cyclotrons and their applications 2001, 16th International Conference. American Institute of Physics Conference Proceedings, vol. 600, May 13-17, 2001, pp. 40-43.
Zherbin et al., Proton Beam Therapy at the Leningrad Synchrocyclotron (Clinicomethodological Aspects and Therapeutic Results), Aug. 1987, 32(8):17-22, (German with English abstract on pp. 21-22).
Second Office Action (Chinese) for CN201380062113.8, 5 pages (dated Jun. 16, 2017).
Second Office Action (English translation) for CN201380062113.8, 7 pages (dated Jun. 16, 2017).

Related Publications (1)

	Number	Date	Country
	20170231081 A1	Aug 2017	US

Provisional Applications (1)

	Number	Date	Country
	61707590	Sep 2012	US

Continuations (1)

	Number	Date	Country
Parent	14039652	Sep 2013	US
Child	15441563		US

Magnetic field regenerator

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

Field of Search

US

International Classifications

Disclaimer

Term Extension

Abstract