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تسجيل مستخدم جديدMIMAC low energy electron-recoil discrimination measured with fast neutrons
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Q. Riffard
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MIMAC (MIcro-TPC MAtrix of Chambers) is a directional WIMP Dark Matter detector project. Direct dark matter experiments need a high level of electron/recoil discrimination to search for nuclear recoils produced by WIMP-nucleus elastic scattering. In this paper, we proposed an original method for electron event rejection based on a multivariate analysis applied to experimental data acquired using monochromatic neutron fields. This analysis shows that a $10^5$ rejection power is reachable for electron/recoil discrimination. Moreover, the efficiency was estimated by a Monte-Carlo simulation showing that a 105 electron rejection power is reached with a $86.49pm 0.17$% nuclear recoil efficiency considering the full energy range and $94.67pm0.19$% considering a 5~keV lower threshold.
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