Claims
- 1. An alpha particle detector that operates by detecting air ions created by collisions with alpha particles comprising:
- an electrically conductive enclosure defining first and second openings for admitting and exhausting air;
- two or more electrical conductors insulatively mounted inside said enclosure;
- means for generating a voltage in one of said electrical conductors, creating an electric field between said two or more electrical conductors;
- fan means mounted outside said enclosure adjacent to said second opening for drawing air containing said air ions through said first opening in said enclosure and across said electric field between said two or more electrical conductors; and
- detecting means connected to another one of said two or more electrical conductors for indicating a current through said another one of said two or more electrical conductors produced by said air ions.
- 2. The alpha particle detector as described in claim 1, wherein said two or more electrical conductors comprise two or more parallel planar electrically conductive meshes.
- 3. The alpha particle detector as described in claim 2, wherein said two or more planar electrically conductive meshes comprise first, second and third parallel planar electrically conductive meshes.
- 4. The alpha particle detector as described in claim 3, wherein said third electrically conductive mesh is grounded.
- 5. The alpha particle detector as described in claim 2, wherein said two or more planar parallel electrically conductive meshes comprise first and second parallel planar electrically conductive meshes.
- 6. The alpha particle detector as described in claim 5, wherein said first planar electrically conductive mesh is connected to said voltage generating means and said second planar electrically conductive mesh is connected to said detecting means.
- 7. The alpha particle detector as described in claim 1, wherein and two or more electrical conductors comprise first and second electrical conductors.
- 8. The detector as described in claim 1, further comprising channel means attached to said second opening for transporting air from a distant location to said detector.
- 9. The detector as described in claim 8, wherein said channel means comprises a conductive inner surface connected to said conductive enclosure.
- 10. The detector as described in claim 1, wherein said means for generating a voltage generates a voltage of at least 100 V in said one of said electrical conductors.
- 11. The alpha particle detector as described in claim 1, wherein said detector is mounted on an electrically conductive booth having ceiling, floor, sides, and first and second doors, and defining openings near said floor allowing air to enter said both.
- 12. The alpha particle detector as described in claim 11, wherein said second door is closed until allowed to be opened by said detecting means after no air ions are detected.
- 13. The alpha particle detector as described in claim 1, wherein said detector is mounted over an opening in an enclosure having air inlet vents.
- 14. The alpha particle detector as described in claim 13, wherein aid enclosure is mounted over a conveyor belt and wherein said conveyor belt comprises means for transporting tools, equipment, or radioactive waste through said enclosure.
- 15. The alpha particle detector as described in claim 1, wherein said detector is mounted over an opening in an enclosure having air inlet vents, or has an open bottom.
- 16. The alpha particle detector as described in claim 1, wherein said detector is mounted over an opening in an enclosure having air inlet vents, which enclosure has openings in a side sized for accepting hands and arms to be monitored for alpha contamination.
- 17. The alpha particle detector as described in claim 1, wherein said detector is mounted over an opening in an enclosure having air inlet vents and having a volume of sufficient size to constitute a decay volume, for monitoring radioactive gas concentrations.
- 18. A method of detecting a distant source of alpha particles comprising the steps of:
- generating a high voltage in a first electrical conductor;
- drawing air containing air ions through an air passage and across a second electrical conductor positioned between said first electrical conductor and said air passage; and
- detecting a current in said second electrical conductor produced by said air ions contacting said second electrical conductor.
Parent Case Info
This is a continuation-in-part application out of U.S. patent application Ser. No. 494,286, entitled "LONG RANGE ALPHA PARTICLE DETECTOR," now abandoned.
Government Interests
The present invention relates to the field of detection of radiation and, more specifically to the detection of alpha particles at a relatively great distance from the point of emission of the alpha particle. The invention is a result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).
US Referenced Citations (5)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
494286 |
Mar 1990 |
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