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تسجيل مستخدم جديدFirst measurement of the Head-Tail directional nuclear recoil signature at energies relevant to WIMP dark matter searches
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We present first evidence for the so-called Head-Tail asymmetry signature of neutron-induced nuclear recoil tracks at energies down to 1.5 keV/amu using the 1m^3 DRIFT-IIc dark matter detector. This regime is appropriate for recoils induced by Weakly Interacting Massive Particle (WIMPs) but one where the differential ionization is poorly understood. We show that the distribution of recoil energies and directions induced here by Cf-252 neutrons matches well that expected from massive WIMPs. The results open a powerful new means of searching for a galactic signature from WIMPs.
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We present the first detailed simulations of the head-tail effect relevant to directional Dark Matter searches. Investigations of the location of the majority of the ionization charge as being either at the beginning half (tail) or at the end half (h
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