APPLICATIONS OF TECHNOLOGY:
- Radiation detection
- High-energy physics
- Medical imaging
- Oil exploration
- X-ray detection
- Extremely high light yield (80,000+ photons/MeV)
- Precise energy resolution
- Rapid response
- Operation at ambient temperatures
Scientists at Berkeley Lab have produced several new high-performance inorganic scintillators that provide a higher and faster light yield (luminosity) than commercially available scintillators. The new scintillators have other characteristics crucial for radioisotope identification: precise energy resolution; very good proportionality; excellent stopping power; high density; and operability at ambient temperatures. These features are particularly important to enable the use of scintillators for security applications, such as detection of radioactive materials. The new scintillators could also be instrumental in high energy physics research and nuclear medicine.
The Berkeley Lab scintillators are crystals of lanthanide doped compounds containing barium in combination with halides, cesium, strontium, silicate, or phosphorous oxide. Each crystal has a different composition to optimize the desired features in detecting radiation. (See Table 1 for representative compositions.) Two of the most promising technologies is IB-2751 (cesium barium halide iodide, barium mixed halide, including bromoiodide, chloroiodide and fluoroiodide), each doped with europium. See Table 2 for performance characteristics of these scintillator technologies. In particular, the luminosity and energy resolutions are significantly better than those of NaI, a scintillator currently used in many detectors.
Representative Compositions of the Scintillator Technologies
Performance Characteristics of IB-2720 and IB-2751
|Mean luminosity(photons/MeV of absorbed gamma radiation)||87,000||97,000|
|Energy resolution(full width half maximum of the 662 keV absorption peak)||4.3%||3.8%|
|Density||5 g/cm3||5 g/cm3|
|Decay time (for more than 80% of the emitted light under X-ray excitation)||Less than 500 nsec||1.2 msec|
DEVELOPMENT STAGE: Bench scale demonstration performed.
STATUS: Issued U. S. Patent Application 8,384,035 (IB-2711). Issued U. S. Patent Application 8,486,300 (IB-2767). Published patent application US2015/0268359 (IB-2720, IB-2751). Available for licensing or collaborative research.
FOR MORE INFORMATION:
Bourret-Courchesne, E.D., G. Bizarri, S.M. Hanrahan, G. Gundiah, Z. Yan, S.E. Derenzo. “BaBrI:Eu2+, a bright scintillator,” Nuclear Instruments and Methods in Physics Res A. 613:95-97 (2010).
Bourret-Courchesne, E.D., G. Bizarri, R. Borade, Z. Yan, S.M. Hanrahan, G. Gundiah, A. Chaudhry, A. Canning, S.E. Derenzo. “Eu2+-doped Ba2CsI5, a new high-performance scintillator,” Nuclear Instruments and Methods in Physics Res A. 612:138-142 (2009).
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
Fast Scintillation Detectors Using Direct-Gap Semiconductors, IB-1833
Neutron Detection Technique Using Layered Semiconductors, IB-2424
Cost Effective Identification of Novel Semiconductor Detector Materials, IB-2199
Co-Planar Electrodes for Radiation Detection, IB-1033
REFERENCE NUMBER: IB-2751, IB-2711, IB-2767