Radiation detector

Patent metadata

Field	Value
Publication number	US-10408951-B2
Application number	US-201715405889-A
Country	US
Kind code	B2
Filing date	Jan 13, 2017
Priority date	Jan 29, 2016
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A radiation detector is provided. In a further aspect, a detector employs a Parallel Plate Avalanche Counter (“OPPAC”) which includes an anode film, a parallel cathode film and multiple optical photo-detectors, such as photo-sensors and/or photo-multipliers. A method of using a radiation detector is also provided.

First claim

The invention claimed is:

1. A radiation detector system comprising:
substantially parallel electrode sheets separated by a gap; and
a scintillating gas located in the gap; and
photo-detectors located adjacent edges of the gap between the electrode sheets;
the photo-detectors operably detecting scintillation light produced during an avalanche process initiated by an ionizing radiation particle crossing the gap between the electrode sheets;
a collimator wall located between an adjacent pair of the photo-detectors and the collimator wall extending inwardly beyond the adjacent pair of the photo-detectors; and
the electrode sheets, gas and photo-detectors being adapted to act as a transmission detector for identification of heavy ions with minimal straggling on an impinging beam.

2. The detector system of claim 1 , further comprising:
a scintillating gas located in the gap; and
the walls located between the photo-detectors operably collimating the scintillation light reaching the photo-detectors.

3. The detector system of claim 2 , wherein the collimating wall is reflective aluminum or Teflon.

4. The detector system of claim 1 , wherein at least one of the electrode sheets includes foil, and the photo-detectors are photodiode sensors.

5. The detector system of claim 1 , wherein at least one of the electrode sheets includes foil, and the photo-detectors are position-sensitive gas photomultipliers.

6. The detector system of claim 2 , wherein an open end defined between each adjacent pair of the walls faces toward an open center between arrays of the photo-detectors.

7. The detector system of claim 1 , wherein:
the gap between the electrode sheets is 10 mm or less; and
the scintillating gas located in the gap includes at least one of: CF 4 , Xe, Ar, TEA, TMEA, N 2 , CO 2 , CH 4 , noble gas, and mixtures thereof.

8. The detector system of claim 1 , wherein the photo-detectors detect gamma rays, and the gap is a drift gap between an outer foil one of the electrodes and a mesh middle one of the electrodes, further comprising another gap between the mesh middle electrode and another outer foil one of the electrodes.

9. The detector system of claim 1 , further comprising a programmable controller connected to the photo-detectors, and instructions stored in non-transient computer memory determining a horizontal and vertical position of ionic particle fragmentation as optically sensed by the photo-detectors.

10. The detector system of claim 1 , further comprising a particle accelerator, the electrode sheets and photo-detectors receiving a particle from the accelerator.

11. The detector system of claim 1 , further comprising a Compton camera, the electrode sheets and photo-detectors being located within the Compton camera.

12. The detector system of claim 1 , wherein the system is part of a non-destructive imaging radiography device, and the sheets are foils.

13. A radiation detector system comprising:
a cathode foil;
an anode foil spaced apart from the cathode foil;
a scintillating gas between the cathode and anode foils;
optical sensors positioned around a central portion between the foils and adjacent multiple peripheral edges of each of the foils; and
collimating walls located between adjacent pairs of the optical sensors adjacent the multiple peripheral edges.

14. The detector system of claim 13 , wherein the collimating walls are reflective aluminum or Teflon.

15. The detector system of claim 13 , wherein there are at least four arrays of the optical sensors with each array being linearly aligned, and the arrays surround the central portion.

16. The detector system of claim 13 , wherein the optical sensors are gas photomultipliers located outboard of opposite peripheral edges of and between parallel planes defined by the foils.

17. The detector system of claim 13 , wherein the optical sensors are photodiodes located outboard of opposite peripheral edges of and between parallel planes defined by the foils.

18. The detector system of claim 13 , wherein:
a gap between the foils is 10 mm or less, and the foils are parallel to each other; and
the scintillating gas includes at least one of: CF 4 , Xe, Ar, TEA, TMEA, noble gas, and mixtures thereof.

19. The detector system of claim 1 , further comprising a superconducting cyclotron coupled to a fragment separator, the foils and optical sensors being located adjacent the fragment separator, and the superconducting cyclotron sending an ion beam having an energy of at least 100 MeV to the fragment separator.

20. A method of using a detector, the method comprising:
(a) emitting a charged particle at a gas located between an anode sheet and a cathode sheet;
(b) creating scintillation light at the gas between the sheets during an avalanche process triggered by the charged particle crossing a gas gap and releasing ionization electrons in the gas;
(c) optically sensing the scintillation light with sensors located adjacent opposite peripheral portions of at least one of the sheets, and sending an associated electrical output signal to a programmable controller; and
(d) determining a position of the charged particle by sensing electroluminescent light during transmission using photo-detectors located adjacent peripheral edges of the gas gap.

21. The method of claim 20 , wherein:
at least one of the sheets includes foil;
the sensors are photodiodes or photo-multipliers;
further comprising linearly aligning multiples of the sensors along each edge of the foil.

22. The method of claim 21 , further comprising collimating at least some of the scintillation light prior to the light reaching the sensors.

23. The method of claim 20 , further comprising using the programmable controller to determine horizontal and vertical position of the charged particles optically sensed by the sensors.

24. The detector system of claim 1 , wherein the system is a hadron-therapy medical transmission detector.

25. The detector system of claim 1 , wherein the system is a proton radiography transmission detector.

26. The detector system of claim 1 , wherein the collimator wall is reflective.

27. The detector system of claim 13 , wherein the collimating walls are reflective to guide light toward the optical sensors.

Assignees

• Univ Michigan State

Inventors

• Cortesi Marco
• Yurkon John E

Classifications

• G01T1/2935

  using ionisation detectors · CPC title

• G01T1/205 Primary

  the detector being a gas · CPC title

• G01T1/2018

  Scintillation-photodiode combinations · CPC title

• G01T1/20183

  Arrangements for preventing or correcting crosstalk, e.g. optical or electrical arrangements for correcting crosstalk · CPC title