Gamma-ray spectroscopy using small, cooled bismuth germanate scintillators and silicon photodiodes

Scintillators Photomultipliers Crystal Scintillators Photomultipliers Gamma Ray Gamma Ray Scattered : Light Emitted Gamma Ray Absorbed : Light Emitted

X-ray spectrometry with Peltier-cooled large area avalanche photodiodes

Performance characteristics of the response of a Peltier-cooled large-area avalanche photodiode are investigated. Detector gain, energy linearity, energy resolution and minimum detectable energy are studied at different operation temperatures. Detector energy resolution and lowest detectable X-ray energy present a strong improvement as the operation temperature is reduced from 25 to 15 C and sl...

Optical simulation and experimental measurement of gamma ray energy spectrum of plastic scintillators with different sizes

The application of large plastic scintillators is widely increasing in the different areas of industry, medicine and security due to technical and economic advantages. One of the main disadvantages of these detectors is the unknown position of Compton edge at gamma ray spectrum. In this research, GEANT4/GATE code has been used to simulate the gamma ray spectrum for different volumes of large pl...

Al0.2Ga0.8As X-ray photodiodes for X-ray spectroscopy

Three custom-made Al0.2Ga0.8As p-i-n mesa X-ray photodiodes (200 μm diameter, 3 μm i layer) were electrically characterised and investigated for their response to illumination with soft X-rays from an Fe radioisotope X-ray source (Mn Kα = 5.9 keV; Mn Kβ = 6.49 keV). The AlGaAs photodiodes were shown to be suitable for photon counting X-ray spectroscopy at room temperature. When coupled to a cus...

Comparing X-ray dose reduction capability of silicon-bismuth micro- and nanocomposite shields using chest CT test

Comparison of radiation shields of different thicknesses and structures (especially different particle sizes of their constituents) is helpful to select an appropriate shield for patient protection in medical imaging tests particularly CT-scan. In this study micro- and nano-powders of bismuth were mixed with silicone matrix to make composite radiation shields for breast. The shields were provid...