TY - JOUR
T1 - Revisiting the dark matter interpretation of excess rates in semiconductors
AU - Abbamonte, Peter
AU - Baxter, Daniel
AU - Kahn, Yonatan
AU - Krnjaic, Gordan
AU - Kurinsky, Noah
AU - Mandava, Bashi
AU - Wagner, Lucas K.
N1 - Publisher Copyright:
© 2022 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"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. Funded by SCOAP3.
PY - 2022/6/15
Y1 - 2022/6/15
N2 - In light of recent results from low-threshold dark matter detectors, we revisit the possibility of a common dark matter origin for multiple excesses across numerous direct detection experiments, with a focus on the excess rates in semiconductor detectors. We explore the interpretation of the low-threshold calorimetric excess rates above 40 eV in the silicon SuperCDMS Cryogenic Phonon Detector and above 100 eV in the germanium EDELWEISS Surface detector as arising from a common but unknown origin, and demonstrate a compatible fit for the observed energy spectra in both experiments, which follow a power law of index a=3.43-0.06+0.11. Despite the intriguing scaling of the normalization of these two excess rates with approximately the square of the mass number A2, we argue that the possibility of common origin by dark matter scattering via nuclear recoils is strongly disfavored, even allowing for exotic condensed matter effects in an as-yet unmeasured kinematic regime, due to the unphysically large dark matter velocity required to give comparable rates in the different energy ranges of the silicon and germanium excesses. We also investigate the possibility of inelastic nuclear scattering by cosmic ray neutrons, solar neutrinos, and photons as the origin, and quantitatively disfavor all three based on known fluxes of particles.
AB - In light of recent results from low-threshold dark matter detectors, we revisit the possibility of a common dark matter origin for multiple excesses across numerous direct detection experiments, with a focus on the excess rates in semiconductor detectors. We explore the interpretation of the low-threshold calorimetric excess rates above 40 eV in the silicon SuperCDMS Cryogenic Phonon Detector and above 100 eV in the germanium EDELWEISS Surface detector as arising from a common but unknown origin, and demonstrate a compatible fit for the observed energy spectra in both experiments, which follow a power law of index a=3.43-0.06+0.11. Despite the intriguing scaling of the normalization of these two excess rates with approximately the square of the mass number A2, we argue that the possibility of common origin by dark matter scattering via nuclear recoils is strongly disfavored, even allowing for exotic condensed matter effects in an as-yet unmeasured kinematic regime, due to the unphysically large dark matter velocity required to give comparable rates in the different energy ranges of the silicon and germanium excesses. We also investigate the possibility of inelastic nuclear scattering by cosmic ray neutrons, solar neutrinos, and photons as the origin, and quantitatively disfavor all three based on known fluxes of particles.
UR - http://www.scopus.com/inward/record.url?scp=85125563814&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85125563814&partnerID=8YFLogxK
U2 - 10.1103/PhysRevD.105.123002
DO - 10.1103/PhysRevD.105.123002
M3 - Article
AN - SCOPUS:85125563814
SN - 2470-0010
VL - 105
JO - Physical Review D
JF - Physical Review D
IS - 12
M1 - 123002
ER -