Gamma-ray spectrometry with thick mercuric iodide detectors

Abstract

Gamma-ray spectra with energies up to 1.3 MeV have been detected for the first time with 1-cm-thick Hg12 semiconductor detectors at room temperature. The spectra can be taken using a "long," 10 vsec, or a llshort,ll 0.5 vsec, charge collection time. The latter has produced better results with better peak efficiency, higher peak-to-valley ratio, and fewer low energy counts with little sacrifice in resolution. Spectra for energies between 100 keV and 1.3 MeV and descriptions of the techniques for their acquisition are presented. The thick detectors need a conditioning treatment, which is described, prior to showing spectral response.-1.

Digital pulse height correction in HgI2γ-ray detectors

“…The effects of ballistic deficit can be minimized to a great extent if the detector pulses are shaped for a duration long enough to ensure complete charge collection. Long shaping times help to achieve a good charge collection only if the carrier lifetime is greater than the transit time [2]. In the case of the present HgI 2 crystals, the lifetime of electrons was estimated to be approximately 20 µs and that of holes was estimated to be greater than 30 µs.…”

Optimization of mercuric iodide platelets growth by the polymer controlled vapor transport method

“…Due to its appropriate physical properties, mercuric iodide is one of the more suitable semiconductor materials for X-ray and Gamma ray detectors operating at room temperature and it is specially useful for low energy X-ray spectrometry [1][2][3][4][5][6][7][8][9] . As X-rays penetrate only about several microns in mercuric iodide crystals 10 , thin crystals of about hundreds of micrometers in thickness are needed for X-ray detection.…”