Axion Portal Dark Matter and the LUX-ZEPLIN High-Recoil Event
- 1Department of Physics , University of Illinois Chicago , Chicago , IL 60607 , USA and Rudolf Peierls Centre for Theoretical Physics ,
- 2University of Oxford , OX1 3NP , UK
Abstract
LUX-ZEPLIN (LZ) has reported one event compatible with a 248 keV nuclear recoil. While initial attention has focused on inelastic dark matter, that interpretation depends sensitively on the uncertain high-speed tail of the Galactic halo. We develop instead an elastic realisation of the pseudoscalar-pseudoscalar interaction L4=(χ̅iγ5χ)(N̅ iγ5N), whose contact templates give one of the largest local significances identified by LZ. The minimal model presented involves Dirac fermion dark matter and a pseudoscalar mediator. The pseudoscalar arises from a complex singlet and the minimal gauge-invariant UV completion also requires a single multi-TeV vector-like heavy quark. A representative model which realises thermal freeze-out has mχ∼ 400 GeV and ma∼ 1 GeV. The simplest model breaks from the isoscalar/isovector assumption, and the recoil spectrum lies between LZ's elastic O4v and contact L4v templates, suggesting a local significance of $2.6−3.2σ$.
Related
- Inelastic Dark Matter from a Higher-Dimensional Operator: The LUX-ZEPLIN High-Recoil Event and Thermal Relic
- Higgsino Dark Matter Interpretation of the LUX-ZEPLIN 248 keV Nuclear-Recoil Event
- The Inert Doublet Model of Dark Matter and the LUX-ZEPLIN High-Recoil Event
- Sub-TeV Singlino Dark Matter in light from Sagittarius A∗ and LUX-ZEPLIN Nuclear-Recoil Event
- ALP-mediated inelastic dark matter and the LUX-ZEPLIN high-recoil candidate event LZ230616
BibTeX
@misc{unwin2026axion,
title = {{Axion Portal Dark Matter and the LUX-ZEPLIN High-Recoil Event}},
author = {James Unwin},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.04186},
eprint = {2609.04186},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.04186},
}
RIS
TY - UNPB
TI - Axion Portal Dark Matter and the LUX-ZEPLIN High-Recoil Event
AU - James Unwin
PY - 2026
DA - 2026/09/03
PB - arXiv
DO - 10.48550/arxiv.2609.04186
UR - https://arxiv.org/abs/2609.04186
AB - LUX-ZEPLIN (LZ) has reported one event compatible with a 248 keV nuclear recoil. While initial attention has focused on inelastic dark matter, that interpretation depends sensitively on the uncertain high-speed tail of the Galactic halo. We develop instead an elastic realisation of the pseudoscalar-pseudoscalar interaction L_4=(χ̅iγ^5χ)(N̅ iγ^5N), whose contact templates give one of the largest local significances identified by LZ. The minimal model presented involves Dirac fermion dark matter and a pseudoscalar mediator. The pseudoscalar arises from a complex singlet and the minimal gauge-invariant UV completion also requires a single multi-TeV vector-like heavy quark. A representative model which realises thermal freeze-out has m_χ∼ 400 GeV and m_a∼ 1 GeV. The simplest model breaks from the isoscalar/isovector assumption, and the recoil spectrum lies between LZ's elastic O_4^v and contact L_4^v templates, suggesting a local significance of $2.6−3.2σ$.
SN - 2331-8422
ER -