Energy calibration and performance testing of LEGe detector

Abstract

The low energy germanium detector (LEGe) is in all aspects optimised for performance at low and moderate energies. It has specific advantages over conventional planar or coaxial detectors. LEGe is a kind of semiconductor detector commonly used in X-ray detection. It can display the spectrum of X-ray and record photon counts. Photon fluence is used to describe the radiation field by recording the number of incident photons. In order to take full advantage of the low energy response of this intrinsically thin window detector, LEGe cryostats are usually equipped with a beryllium window, thin front and side contact allowing spectroscopy from 3 keV and above. The rear contact is of less than full area which gives a lower detector capacitance compared to a planar device of similar size. It is widely used in low energy gamma spectroscopy, X-ray absorption spectroscopy, nuclear safeguards or X-ray fluorescence spectrometer and X-ray diffraction. Spectrum is an intuitional and accurate description of X-ray radiation. In this work, experiment was carried out to calibrate the detector and test the spectrum, and then to calculate the energy resolution. The experiment results about energy resolution (full width at half maximum) are 222 eV (@5.9 keV) and 519 eV (@122 keV).