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arXiv · 1511.05816

Studies of THGEM-based detector at low-pressure Hydrogen/Deuterium, for AT-TPC applications

Abstract

We study the performance of single- and double- THick Gas Electron Multiplier (THGEM) detectors in pure Hydrogen and Deuterium at low pressures, in the range of 100-450 Torr. The effect of the pressure on the maximum achievable gain, ion-back flow and long-term gain stability are investigated for single and double cascade detectors. In particular, it was found that maximum achievable gains above 10^4, from single-photoelectrons avalanche, can be achieved for pressures of 200 Torr and above; for lower pressure the gains are limited by avalanche-induced secondary effects to a values of around 103. The results of this work are relevant in the field of avalanche mechanism in low-pressure, low-mass noble gases, in particular for applications of THGEM end-cap readout for active-target Time Projection Chambers (TPC) in the field of nuclear physics and nuclear astrophysics.

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Marco Cortesi, John Yurkon, Wolfgang Mittig, Daniel Bazin, Saul Beceiro-Novo, Andreas Stolz. 2015-11-18. Studies of THGEM-based detector at low-pressure Hydrogen/Deuterium, for AT-TPC applications. https://doi.org/10.1088/1748-0221%2F2015%2F09%2Fp09020

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