Ionization produced by low-energy nuclear recoils is among the primary direct signatures of dark matter interactions. Despite the urgency of dark matter detection and the recent measurements of coherent elastic neutrino-nucleus scattering, detector response to nuclear recoils is not well characterized in the keVnr and sub-keVnr regime across a variety of materials. We have re-performed a measurement of the ionization produced by monoenergetic 254 eVnr nuclear recoils in Ge with improved digital electronics and additional systematic studies. Our results indicate an ionization yield of 64 +/- 8 eVee corresponding to a quenching factor of 25 +/- 3%, greater than the 14% predicted by the Lindhard model. This ionization enhancement could greatly improve the sensitivity of high-purity Ge detectors in dark matter detection and measurement of neutrinos via coherent scattering.
@article{arxiv.2405.10405,
title = {Measurement of Ionization Produced by 254 eVnr Nuclear Recoils in Germanium},
author = {A. R. L. Kavner and I. Jovanovic},
journal= {arXiv preprint arXiv:2405.10405},
year = {2024}
}