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arXiv · 1803.07803

A low-energy sensitive compact gamma-ray detector based on LaBr3 and SiPM for GECAM

P. Lv·S. L. Xiong·X. L. Sun·J. G. Lv·Y. G. Li
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Abstract

The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) project is the planned Chinese space telescope for detecting the X and gamma-ray counterpart. It consists of two micro-satellites in low earth orbit with the advantages of instantaneous full-sky coverage, low energy threshold down to 6 keV and can be achieved within a short period and small budget. Due to the limitation of size, weight and power consumption of micro-satellites, silicon photomultipliers (SiPMs) are used to replace the photomultiplier tubes (PMTs) to assemble a novel gamma-ray detector. A prototype of a SiPM array with LaBr3 crystal is built and tested, and it shows a high detection efficiency (70% at 5.9 keV) and an acceptable uniformity. The low-energy X-ray of 5.9 keV can be detected by a simply readout circuit, and the energy resolution is 6.5% (FWHM) at 662 keV. The design and performance of the detector are discussed in detail in this paper.

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P. Lv, S. L. Xiong, X. L. Sun, J. G. Lv, Y. G. Li. 2018-09-14. A low-energy sensitive compact gamma-ray detector based on LaBr3 and SiPM for GECAM. https://doi.org/10.1088/1748-0221%2F13%2F08%2Fp08014

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