Electrovolt-scale backgrounds from surfaces

Alan E. Robinson

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arXiv · 2010.11043

Electrovolt-scale backgrounds from surfaces

Alan E. Robinson

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Abstract

Recent results from the SENSEI experiment show that a cut on event clustering can reduce low-energy excesses in their eV-sensitive calorimeter. This hints at the role of surrounding uninstrumented surfaces in producing backgrounds. Charged particles crossing dielectric boundaries are well known to produce low-energy radiation. In particular, transition radiation, secondary electron emission, and sputtering may contribute to the spectrum, morphology, and rate of events observed in eV-sensitive detectors. The rich phenomenology and high yields of these surface processes will complicate comparisons of low-threshold dark matter detectors both to each other and to background models.

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Alan E. Robinson. 2020-10-21. Electrovolt-scale backgrounds from surfaces. https://arxiv.org/abs/2010.11043

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