Hadrophilic inelastic freeze-in dark matter in q1−q2 gauge extension and the high energy LZ event
Abstract
The recent observation of a single event at nuclear recoil energy 248±23±23 keV by the LZ collaboration has prompted dark matter (DM) model builders to explore new physics explanations. While most of the existing literature invokes an endothermic scattering by a TeV-scale DM to explain the event, the favored DM interaction strength is in tension with the indirect detection constraints for most of the models. To evade this, this work explores exothermic DM scattering in a hadrophilic q1−q2 gauge extension setup with a new Z' boson as a mediator to the dark sector. This can naturally escape the indirect searches in the absence of tree-level coupling of the mediator to neutrinos, W,τ, and b quark. We consider freeze-in production at a low reheating temperature to populate DM in the early universe, with a comparatively smaller coupling than the thermal freeze-out scenario. We identify the Z' parameter space that can explain the observed relic density and LZ event simultaneously. We also discuss the relevant constraints coming from flavor mixing and FCNC.
Related
- Freeze-in of anapole and charge-radius inelastic dark matter: X-ray probes of a decoupled vector portal
- Kaon Portal to Freeze-in Dark Matter
- Direct detection constraints on EFT operators for inelastic dark matter
- Inelastic Signatures of Electroweak Dark Matter
- Solar Neutrino Constraints on Inelastic Dark Matter Scattering in Light of Recent LUX-ZEPLIN Observations
BibTeX
@misc{he2026hadrophilic,
title = {{Hadrophilic inelastic freeze-in dark matter in $q_1-q_2$ gauge extension and the high energy LZ event}},
author = {Xiao-Gang He and Xuan Hong and Sk Jeesun},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.15714},
eprint = {2609.15714},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.15714},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Hadrophilic inelastic freeze-in dark matter in q_1−q_2 gauge extension and the high energy LZ event
AU - Xiao-Gang He
AU - Xuan Hong
AU - Sk Jeesun
PY - 2026
DA - 2026/09/14
PB - arXiv
DO - 10.48550/arxiv.2609.15714
UR - https://arxiv.org/abs/2609.15714
AB - The recent observation of a single event at nuclear recoil energy 248±23±23 keV by the LZ collaboration has prompted dark matter (DM) model builders to explore new physics explanations. While most of the existing literature invokes an endothermic scattering by a TeV-scale DM to explain the event, the favored DM interaction strength is in tension with the indirect detection constraints for most of the models. To evade this, this work explores exothermic DM scattering in a hadrophilic q_1−q_2 gauge extension setup with a new Z' boson as a mediator to the dark sector. This can naturally escape the indirect searches in the absence of tree-level coupling of the mediator to neutrinos, W,τ, and b quark. We consider freeze-in production at a low reheating temperature to populate DM in the early universe, with a comparatively smaller coupling than the thermal freeze-out scenario. We identify the Z' parameter space that can explain the observed relic density and LZ event simultaneously. We also discuss the relevant constraints coming from flavor mixing and FCNC.
ER -