Abstract
Coherent elastic neutrino-nucleus scattering and low-mass dark matter detectors rely crucially on the understanding of their response to nuclear recoils. We report the first observation of a nuclear recoil peak at around 112 eV induced by neutron capture. The measurement was performed with a cryogenic detector from the NUCLEUS experiment exposed to a source placed in a compact moderator. We identify the expected peak structure from the single- de-excitation of with and its origin by neutron capture with significance. This result demonstrates a new method for precise, in situ, and nonintrusive calibration of low-threshold experiments.
- Received 9 November 2022
- Revised 12 February 2023
- Accepted 13 April 2023
DOI:https://doi.org/10.1103/PhysRevLett.130.211802
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society