A Comprehensive Interpretation of the LZ High-Energy Recoil Event: A Minimal U(1)B Dark Sector and Its Experimental Tests
Abstract
The $248$ keV nuclear-recoil candidate reported by LUX-ZEPLIN (LZ) motivates an inelastic dark matter (DM) interpretation, in which scattering converts the DM particle into a slightly heavier state. We provide a comprehensive study of this interpretation in an anomaly-free model of gauged baryon number, where a new vector boson, ZB, mediates interactions between DM and quarks. Breaking the baryonic gauge symmetry generates the new particle masses and a small splitting between two DM states, while a residual symmetry keeps the lighter state stable. We identify regions compatible with the LZ candidate, the observed DM abundance, and current ATLAS and CMS dijet constraints. Within the scanned domain, these regions span DM masses mχ≃0.19-$4.5$ TeV, mediator masses MZB≃0.05-$5.0$ TeV, and gauge couplings gB≃0.004-$0.74$, with correlated values of these parameters. A representative thermal solution has mχ=1 TeV, MZB=1.44 TeV, gB≃0.228, and a mass splitting of $300$ keV. A small electroweak mixing allows the heavier DM state to decay rapidly, suppressing unwanted signals from its surviving population. This interpretation can be tested through complementary measurements: additional LZ and XENONnT data can establish whether the high-energy recoil signal persists, ATLAS and CMS Run-3 dijet searches can probe the mediator mass and coupling, and a dedicated IceCube analysis of four-quark final states can test DM capture and annihilation in the Sun. Together, these measurements can test complementary parts of the surviving region and assess whether the LZ candidate is consistent with this interpretation.
Related
- A Vector-Like Lepton Interpretation of the High-Energy Nuclear Recoil Candidate in LUX-ZEPLIN
- Higgsino Dark Matter Interpretation of the LUX-ZEPLIN 248 keV Nuclear-Recoil Event
- Sub-MeV gamma-ray lines from an endothermic interpretation of the LZ recoil candidate
- Testing Higgs-Coupled Minimal Dark Matter with Solar Neutrinos after the LZ High-Recoil Event
- Higgsino dark matter compatible with the LUX-ZEPLIN high-energy nuclear-recoil event and IceCube constraints
BibTeX
@misc{mauro2026comprehensive,
title = {{A Comprehensive Interpretation of the LZ High-Energy Recoil Event: A Minimal $U(1)_B$ Dark Sector and Its Experimental Tests}},
author = {Mattia Di Mauro},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.14188},
eprint = {2610.14188},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.14188},
}
RIS
TY - UNPB
TI - A Comprehensive Interpretation of the LZ High-Energy Recoil Event: A Minimal U(1)_B Dark Sector and Its Experimental Tests
AU - Mattia Di Mauro
PY - 2026
DA - 2026/10/09
PB - arXiv
DO - 10.48550/arxiv.2610.14188
UR - https://arxiv.org/abs/2610.14188
AB - The $248$ keV nuclear-recoil candidate reported by LUX-ZEPLIN (LZ) motivates an inelastic dark matter (DM) interpretation, in which scattering converts the DM particle into a slightly heavier state. We provide a comprehensive study of this interpretation in an anomaly-free model of gauged baryon number, where a new vector boson, Z_B, mediates interactions between DM and quarks. Breaking the baryonic gauge symmetry generates the new particle masses and a small splitting between two DM states, while a residual symmetry keeps the lighter state stable. We identify regions compatible with the LZ candidate, the observed DM abundance, and current ATLAS and CMS dijet constraints. Within the scanned domain, these regions span DM masses m_χ≃0.19-$4.5$ TeV, mediator masses M_Z_B≃0.05-$5.0$ TeV, and gauge couplings g_B≃0.004-$0.74$, with correlated values of these parameters. A representative thermal solution has m_χ=1 TeV, M_Z_B=1.44 TeV, g_B≃0.228, and a mass splitting of $300$ keV. A small electroweak mixing allows the heavier DM state to decay rapidly, suppressing unwanted signals from its surviving population. This interpretation can be tested through complementary measurements: additional LZ and XENONnT data can establish whether the high-energy recoil signal persists, ATLAS and CMS Run-3 dijet searches can probe the mediator mass and coupling, and a dedicated IceCube analysis of four-quark final states can test DM capture and annihilation in the Sun. Together, these measurements can test complementary parts of the surviving region and assess whether the LZ candidate is consistent with this interpretation.
ER -