Lanthanide halide alloys have recently enabled scintillating gamma ray spectrometers comparable to room-temperature
semiconductors (< 3% FWHM energy resolutions at 662keV). However brittle fracture of these materials
hinders the growth of large volume crystals. Efforts to improve the strength through non-lanthanide alloy substitution,
while preserving scintillation, are being pursued. Isovalent alloys nominal Ce0.9Al0.1Br3, Ce0.9Ga0.1Br3, Ce0.9Sc0.1Br3,
Ce0.9In0.1Br3 and Ce0.8Y0.2Br3, as well as aliovalent alloys nominal (CeBr3)0.99(CdCl2)0.01, (CeBr3)0.99(CdBr2)0.01,
(CeBr3)0.99(ZnBr2)0.01, (CeBr3)0.99(CaBr2)0.01, (CeBr3)0.99(SrBr2)0.01, (CeBr3)0.99(PbBr2)0.01, (CeBr3)0.99(ZrBr4)0.01,
(CeBr3)0.99(HfBr4)0.01 were prepared. All of these alloys exhibit bright fluorescence under UV excitation, with varying
shifts in the spectral peaks and intensities relative to pure CeBr3. Further, these alloys scintillate when coupled to a
photomultiplier tube (PMT) and exposed to 137Cs gamma rays. These data and the potential for improved crystal growth
will be discussed.
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