Cesium and lithium-containing quaternary compound scintillators

• US 7,655,919 B1
• Filed: 11/09/2007
• Issued: 02/02/2010
• Est. Priority Date: 11/09/2007
• Status: Active Grant

• Current Assignee: Radiation Monitoring Devices, Inc. (Dynasil Corp. of America)
• Original Assignee: Radiation Monitoring Devices, Inc. (Dynasil Corp. of America)
• Inventors: Van Loef, Edgar V, Higgins, William M, Glodo, Jaroslaw, Shah, Kanai S.
• Primary Examiner(s): Porta; David P
• Assistant Examiner(s): Malevic; Djura
• Application Number:
  US11/938,176
• Time in Patent Office: 816 Days
• Field of Search: 250/370.11
• US Class Current: 250/370.11
• CPC Class Codes: G01T 1/202 the detector being a crystal

Abstract

The present invention relates to quaternary compound scintillators and related devices and methods. The scintillators may include, for example, a quaternary compound, the quaternary compound having a first position, a second position, a third position, a fourth position; wherein the first position is Cs; the second position is Li; the third position is La or Lu; and the fourth position is Cl, Br, or I. In certain embodiments, the scintillator composition can further include a single dopant or mixture of dopants.

Claims

1. A scintillator, comprising a quaternary compound and a dopant, the quaternary compound consisting of a first position, a second position, a third position, a fourth position;

wherein the first position is Cs;

the second position is Li;

the third position is La or Lu; and

the fourth position is Br, or I.

2. The scintillator of claim 1, wherein the dopant comprises Ce, Lu, La, Eu, Pr, Sm Sr, Tl, Cl, F, or I.

3. The scintillator of claim 2, wherein the dopant is present from about 0.1% to about 20% by molar weight.

4. The scintillator of claim 1, wherein the dopant is Ce and present from about 0.1% to about 5% by molar weight.

5. The scintillator of claim 1, wherein the quaternary compound and the dopant comprise Cs2LiLaBr6:

Ce, Cs2LiLaI6;

Ce, or Cs2LiLuI6;

Ce.

6. The scintillator of claim 1, wherein the scintillator is a fast scintillator.

7. The scintillator of claim 6, wherein the scintillator comprises a fast decay-time constant of less than about 90 ns.

8. The scintillator of claim 1, wherein the scintillator comprises a light output of greater than about 10,000 Photons/MeV.

9. The scintillator of claim 1, wherein the scintillator comprises a light output of greater than about 45,000 Photons/MeV.

10. The scintillator of claim 1, wherein the scintillator comprises a sensitivity to both energetic photons and to neutrons.

11. A radiation detection device, comprising a scintillator comprising a quaternary compound and a dopant, the quaternary compound comprising Cs2LiLaBr6:

Ce, Cs2LiLaI6;

Ce, or Cs2LiLuI6;

Ce; and

a photodetector assembly optically coupled to the scintillator.

12. The device of claim 11, wherein the device is configured to detect x-rays, gamma-rays, neutron emissions, or a combination thereof.

13. The device of claim 11, further comprising a radiation source.

14. The device of claim 11, further comprising a computer system coupled to the photodetector assembly so that the computer outputs image data in response to detected radiation.

15. The device of claim 11, wherein the computer comprises instructions for constructing an image from detected radiation.

16. The device of claim 11, wherein the photodetector assembly comprises a photomultiplier tube, a photodiode, a PIN detector, charge-coupled device, or an avalanche detector.

17. A gamma-ray and neutron detection device, comprising:

a scintillator comprising a quaternary compound and a dopant, the quaternary compound consisting of a first position, a second position, a third position, a fourth position;

wherein the first position is Cs;

the second position is Li;

the third position is La or Lu; and

the fourth position is Br, or I;

a photodetector assembly optically coupled to the scintillator; and

electronics configured for performing pulse-shape analysis to differentiate gamma-ray detections from neutron detections.

18. The device of claim 17, further comprising a radiation source.

19. The device of claim 17, further comprising a computer system coupled to the photodetector assembly so that the computer outputs image data in response to detected radiation.

20. The device of claim 17, wherein the scintillator further comprises a reflective layer, a moisture resistant layer, or a vapor barrier.

21. A method of performing radiation detection, comprising:

providing a detection device comprising a scintillator comprising a quaternary compound and a dopant, the quaternary compound consisting of a first position, a second position, a third position, a fourth position;

wherein the first position is Cs;

the second position is Li;

the third position is La or Lu; and

the fourth position is Br, or I; and

a photodetector assembly optically coupled to the scintillator; and

positioning the device such that a radiation source is within a field of view of the scintillator so as to detect emissions from the source.

22. The method of claim 21, wherein a patient is positioned between the radiation source and the scintillator.

23. The method of claim 21, wherein the radiation source comprises a patient.

24. The method of claim 21, wherein the emissions comprise gamma-ray or X-ray emissions.

25. The method of claim 24, wherein the emissions further comprise neutron emissions.

26. A scintillator composition, comprising a quaternary compound and a dopant, where the quaternary compound is a CsLiLu Halide and the halide includes Cl, Br, or I.