Cerium Bromide For Gamma Ray Detection
Radiation detection instruments such as Personal Radiation Detectors (PRDs), Spectroscopic Personal Radiation Detectors (SPRDs) and Radiation Isotope Identification Devices (RIIDs) are used to detect the presence of radioactive materials. Detection of Special Nuclear Materials (SNMs), such as weapon-grade plutonium and highly enriched uranium, can be done by their characteristic gamma-ray radiation signatures. It provides first responders the ability to not only detect the presence of a nuclear source, but to identify the specific SNM.
Until recently, Lanthanum Bromide (LaBr3) was the standard for high end gamma-ray spectroscopy using inorganic scintillator crystals. Unfortunately, Lanthanum (III) Bromide (LaBr3) has one major drawback – the crystal itself is radioactive. This causes background noise that lowers the overall sensitivity for low event rates, which is commonly the case when trying to detect SNMs. To eliminate this problem, RMD developed Cerium Bromide (CeBr3), a new material that had all of the positive qualities of LaBr3 but without the background noise.
Properties of CeBr3
Similar to LaBr3, CeBr3 possesses many desirable properties such as high light yield, fast response, and high density. Energy resolution for CeBr3 is also exemplary. The key advantage of CeBr3 is the very little intrinsic background noise (20 times lower than LaBr3). The ultra-fast response without any slow component is also a major advantage.
Licensing Cerium Bromide
RMD has licensed its patent on a worldwide basis to Hellma Materials. Hellma has perfected the manufacturing process for CeBr3, producing scintillators that meet the highest industry standards for quality and price. They are currently shipping 1, 2 and 3 inch CeBr3 detectors for nuclear nonproliferation, medical imaging systems, and oil well logging. Additionally, Berkeley Nucleonics Corporation (BNC) has also chosen CeBr3 for use in their SAM 940 and SAM 945 RIID.