Higgsino dark matter compatible with the LUX-ZEPLIN high-energy nuclear-recoil event and IceCube constraints
Abstract
We examine Higgsino dark matter (DM) as a potential explanation of the 248 keV nuclear-recoil event of interest reported by the LUX-ZEPLIN (LZ) experiment, taking into account IceCube constraints on DM annihilation in the Sun. In the nearly pure Higgsino limit, two neutral Majorana states separated by a small mass splitting δ are connected by an off-diagonal coupling to the Z boson, providing a natural realization of inelastic DM. Using a likelihood analysis, we identify 90\% confidence regions compatible with the LZ event and consistent with the null results of IceCube searches, both with and without including a constraint from the absence of events in the LZ high-energy sideband. In our LZ analysis, we consider the DM distribution in the Standard Halo Model alone as well as possible enhancements of the high-speed tail induced by the Large Magellanic Cloud (LMC). We present four variants of bounds from IceCube on Higgsino dark matter, depending on various assumptions on cooling channels in the Sun, motivated by severe theoretical uncertainties about Higgsino-nucleon elastic scattering (unimportant for direct detection but crucial for IceCube bounds). Whereas the thermal Higgsino with a mass of 1.1 TeV remains only marginally compatible with both the LZ event and the IceCube limits when the LMC-induced high-speed tail is included and both elastic cooling in the Sun and the LZ high-energy sideband constraint are neglected, higher mass Higgsinos are excellent candidates for the LZ event in light of IceCube constraints. Depending on the halo distribution, cooling interactions, and whether the LZ high-energy sideband is included, the compatible regions in the Higgsino parameter space (mχ,δ) extend from masses of ∼2 TeV to hundreds of TeV or higher, with mass splittings ranging approximately from $350$ to 525 keV.
Related
- Higgsino Dark Matter Interpretation of the LUX-ZEPLIN 248 keV Nuclear-Recoil Event
- Strong Constraints on Higgsino Dark Matter from Solar Capture
- Higgsino dark matter in the Starobinsky supergravity with the MSSM in light of the LUX-ZEPLIN event
- Heavy Higgsino Dark Matter With Low Reheating in View of the LZ High-Recoil Event
- Heavy Higgsino Dark Matter at the Scale of the Vanishing Higgs Quartic
BibTeX
@misc{freese2026higgsino,
title = {{Higgsino dark matter compatible with the LUX-ZEPLIN high-energy nuclear-recoil event and IceCube constraints}},
author = {Katherine Freese and Dionysios P. Theodosopoulos},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.03692},
eprint = {2610.03692},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.03692},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Higgsino dark matter compatible with the LUX-ZEPLIN high-energy nuclear-recoil event and IceCube constraints
AU - Katherine Freese
AU - Dionysios P. Theodosopoulos
PY - 2026
DA - 2026/10/02
PB - arXiv
DO - 10.48550/arxiv.2610.03692
UR - https://arxiv.org/abs/2610.03692
AB - We examine Higgsino dark matter (DM) as a potential explanation of the 248 keV nuclear-recoil event of interest reported by the LUX-ZEPLIN (LZ) experiment, taking into account IceCube constraints on DM annihilation in the Sun. In the nearly pure Higgsino limit, two neutral Majorana states separated by a small mass splitting δ are connected by an off-diagonal coupling to the Z boson, providing a natural realization of inelastic DM. Using a likelihood analysis, we identify 90\% confidence regions compatible with the LZ event and consistent with the null results of IceCube searches, both with and without including a constraint from the absence of events in the LZ high-energy sideband. In our LZ analysis, we consider the DM distribution in the Standard Halo Model alone as well as possible enhancements of the high-speed tail induced by the Large Magellanic Cloud (LMC). We present four variants of bounds from IceCube on Higgsino dark matter, depending on various assumptions on cooling channels in the Sun, motivated by severe theoretical uncertainties about Higgsino-nucleon elastic scattering (unimportant for direct detection but crucial for IceCube bounds). Whereas the thermal Higgsino with a mass of 1.1 TeV remains only marginally compatible with both the LZ event and the IceCube limits when the LMC-induced high-speed tail is included and both elastic cooling in the Sun and the LZ high-energy sideband constraint are neglected, higher mass Higgsinos are excellent candidates for the LZ event in light of IceCube constraints. Depending on the halo distribution, cooling interactions, and whether the LZ high-energy sideband is included, the compatible regions in the Higgsino parameter space (m_χ,δ) extend from masses of ∼2 TeV to hundreds of TeV or higher, with mass splittings ranging approximately from $350$ to 525 keV.
ER -