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arXiv · 2102.10089

Germanium response to sub-keV nuclear recoils: a multipronged experimental characterization

J. I. Collar·A. R. L. Kavner·C. M. Lewis
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Abstract

Germanium is the detector material of choice in many rare-event searches looking for low-energy nuclear recoils induced by dark matter particles or neutrinos. We perform a systematic exploration of its quenching factor for sub-keV nuclear recoils, using multiple techniques: photo-neutron sources, recoils from gamma-emission following thermal neutron capture, and a monochromatic filtered neutron beam. Our results point to a marked deviation from the predictions of the Lindhard model in this mostly unexplored energy range. We comment on the compatibility of our data with low-energy processes such as the Migdal effect, and on the impact of our measurements on upcoming searches.

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J. I. Collar, A. R. L. Kavner, C. M. Lewis. 2021-02-19. Germanium response to sub-keV nuclear recoils: a multipronged experimental characterization. https://doi.org/10.1103/physrevd.103.122003

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