# Constraints on Fermionic Dark Matter Absorption from Radiochemical Solar-Neutrino Measurements

Source: [Constraints on Fermionic Dark Matter Absorption from Radiochemical Solar-Neutrino Measurements](<https://www.sota2.com/research/paper/698abb6fc97a0b3e3b5dde68>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2026-04-30T05:00:12.460Z

Authors: K. Ishidoshiro, K. Tachibana

Published: 2026-02-07T05:56:50.000Z

## Abstract

We reinterpret classic radiochemical solar-neutrino measurements as \`\`rate meters'' for additional, non-negative capture-like contributions induced by fermionic dark matter absorption. Using the chlorine and gallium production-rate data, we build a Bayesian likelihood that accounts for the dominant uncertainties in the solar-neutrino capture-rate prediction (solar fluxes, oscillation parameters, and capture cross sections). Solar-model metallicity systematics are made explicit by presenting results for both the B16--GS98 and B16--AGSS09met solar-model realizations. From the 1D marginalized posteriors of the joint $(R\_{\\chi,\\mathrm{Cl}},R\_{\\chi,\\mathrm{Ga}})$ analysis, we obtain 90\\% upper limits on additional capture-like rate contributions, dominated by chlorine: $R\_{\\chi,\\mathrm{Cl},90}\\simeq 0.388~\\mathrm{SNU}$ (B16--GS98) and $0.588~\\mathrm{SNU}$ (B16--AGSS09met). In the charged-current V--A benchmark, we map these constraints onto upper bounds on $y\\equiv m\_\\chi^2/(4\\pi\\Lambda^4)$ for $m\_\\chi$ above the ${}^{71}$Ga and ${}^{37}$Cl capture thresholds, using a pep-normalized operator mapping anchored to solar-neutrino capture inputs, where $m\_\\chi$ is the dark matter mass and $\\Lambda$ is the effective scale suppressing the charged-current operator. At $m\_\\chi\\simeq 1~\\mathrm{MeV}$, we find $y\_{90}\\simeq 4.88\\times 10^{-49}~\\mathrm{cm}^2$ (B16--GS98) and $7.08\\times 10^{-49}~\\mathrm{cm}^2$ (B16--AGSS09met). These radiochemical bounds are complementary to xenon-based absorption searches and collider interpretations by probing distinct nuclear targets with minimal reliance on spectral reconstruction.

## Recorded benchmark results

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/2602.07384>)

[PDF](<https://arxiv.org/pdf/2602.07384.pdf>)