Fabrication and spectroscopy results of mercuric iodide Frisch collar detectors

A tetragonal prismatic HgI2 crystal grown with low molecular weight ( M ¯ w ) polyethylene addition in a horizontal furnace has been fabricated into a 2.1×2.1×4.1 mm3 Frisch collar spectrometer. With no electronic correction nor LN2 cooling, an energy resolution of 1.8% FWHM at 662 keV (137Cs) is achieved. Spectra from 241Am (4.7% FWHM at 59.5 keV), 57Co (4.0% FWHM at 122 keV), 133Ba (4.4% FWHM at 80 keV and 2.5% FWHM at 356 keV), 198Au (2.6% FWHM at 411 keV), and 60Co (1.2% FWHM at 1173 keV) are also reported.