Limits on Primordial Black Hole Evaporation from LUX-ZEPLIN
Abstract
The LUX-ZEPLIN (LZ) collaboration recently reported a singular anomalous nuclear recoil event at 248 ± 23 keV, accompanied by a strict null result for unexplained excesses in their primary 5.4−50 keV search window. The macroscopic momentum transfer required to generate this event is kinematically inaccessible to standard halo cold dark matter (CDM), naturally motivating models featuring light, relativistic relics. In this work, we investigate whether a contemporary flux of Hawking-boosted dark matter (DM) emitted by evaporating Primordial Black Holes (PBHs) in the $10^{11}-10^{13} \, \rm g $ mass range can source the anomaly. By parameterizing the nuclear scattering with heavy non-relativistic effective field theory (NREFT) operators and endothermic inelastic mass transitions, we formulate a strict kinematic exclusion. We demonstrate that the inherent thermal nature of the Hawking emission, coupled with the relativistic kinematics of the incident flux, inevitably overproduces low-energy recoils, aggressively violating the LZ background bounds. Utilizing this failure, we map the LZ low-energy null results into novel, highly stringent upper limits on the PBH abundance fraction, excluding fPBH ≳ 10−6 for $M_{\rm PBH} \sim 2 \times 10^{11} \, \rm g $ at $ 90 \% $ confidence level.
Related
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- Wide-field search for submicrosecond optical and gamma transients as manifestation of primordial black holes evaporation with the TAIGA-HiSCORE Cherenkov array
BibTeX
@misc{kalita2026limits,
title = {{Limits on Primordial Black Hole Evaporation from LUX-ZEPLIN}},
author = {Jitumani Kalita},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2609.29462},
eprint = {2609.29462},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.29462},
}
RIS
TY - UNPB
TI - Limits on Primordial Black Hole Evaporation from LUX-ZEPLIN
AU - Jitumani Kalita
PY - 2026
DA - 2026/10/01
PB - arXiv
DO - 10.48550/arxiv.2609.29462
UR - https://arxiv.org/abs/2609.29462
AB - The LUX-ZEPLIN (LZ) collaboration recently reported a singular anomalous nuclear recoil event at 248 ± 23 keV, accompanied by a strict null result for unexplained excesses in their primary 5.4−50 keV search window. The macroscopic momentum transfer required to generate this event is kinematically inaccessible to standard halo cold dark matter (CDM), naturally motivating models featuring light, relativistic relics. In this work, we investigate whether a contemporary flux of Hawking-boosted dark matter (DM) emitted by evaporating Primordial Black Holes (PBHs) in the $10^{11}-10^{13} \, \rm g $ mass range can source the anomaly. By parameterizing the nuclear scattering with heavy non-relativistic effective field theory (NREFT) operators and endothermic inelastic mass transitions, we formulate a strict kinematic exclusion. We demonstrate that the inherent thermal nature of the Hawking emission, coupled with the relativistic kinematics of the incident flux, inevitably overproduces low-energy recoils, aggressively violating the LZ background bounds. Utilizing this failure, we map the LZ low-energy null results into novel, highly stringent upper limits on the PBH abundance fraction, excluding f_PBH ≳ 10^−6 for $M_{\rm PBH} \sim 2 \times 10^{11} \, \rm g $ at $ 90 \% $ confidence level.
ER -