NSF Award
2407057
This award supports the installation of a helium-recovery system at the John D. Fox Superconducting Accelerator Laboratory (Fox Lab) on the campus of Florida State University. The Fox Laboratory is one of the nation’s most important training grounds for nuclear scientists at both the Ph.D. and undergraduate levels. Liquefied helium is used to cool the accelerator structures to a temperature a few degrees above absolute zero, at which point they become superconducting. This superconducting accelerator is used to accelerate atomic nuclei, which are then used to perform experiments that explore the nuclear reactions that take place in stars and the ways in which the forces between protons and neutrons cause novel phenomena within nuclei. Twice a year, the accelerator is warmed for regular maintenance and approximately 45% of the helium inventory is lost. The helium recovery system supported by this grant will eliminate losses during scheduled or accidental warm-ups, like those that occur during power outages, mitigating a significant and rapidly growing cost in operating the Fox Lab. The helium-recovery system supported by this grant will allow for more efficient operation and more flexible scheduling at the accelerator, which serves scientists and graduate students at FSU as well as visitors from several universities and national laboratories. <br/><br/>This project supports the installation of a helium-recovery system at the John D. Fox Superconducting Accelerator Laboratory (Fox Lab) on the campus of Florida State University. The Fox Lab accelerator system consists of a Tandem Van de Graaff accelerator boosted by a superconducting Linear Accelerator (Linac). The FSU group of six tenure-line faculty, their graduate students, as well as external groups from Louisiana State University and Oak Ridge National Laboratory have developed the experimental facilities at the laboratory. The laboratory operates three signature programs, the RESOLUT radioactive beam facility, the Super-Enge Split-Pole spectrograph and the Clarion-2 Compton-suppressed germanium detector array. The FSU laboratory is the only heavy-ion nuclear physics laboratory in the southeastern USA and is one of the nation’s most important training grounds for nuclear scientists at both the Ph.D. and undergraduate levels. The researchers working at the Fox Lab pursue two primary scientific goals. The first goal is to reproduce in the laboratory the nuclear reactions that take place in stellar explosions, which produce the majority of heavy elements in the universe. The second goal is to measure the behavior of exotic nuclei – that is, isotopes in which the ratio of neutrons to protons is either too large to be stable (and therefore naturally occurring) or too small to be stable and provide rigorous tests of our understanding of the behavior of all nuclei. The cryogenic operation of the superconducting linac is affected by the increasing costs for helium, which likely will soon become the laboratory’s largest cryogenic expense. The system acquired through this grant will enable an essentially helium-loss-free operation of the accelerator, by recovering and purifying helium that currently would be lost when the facility is warmed up, which typically occurs twice a year. In addition, the recovery system will be backed-up by an electrical generator, avoiding helium loss during unforeseeable power disruptions. We estimate that the proposed system will recycle the equivalent of 1850 liter of liquid helium per year, which otherwise would be lost.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
