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arXiv · 2607.15020

High resolution Lyman-{\alpha} forest constraints on dark matter-neutrino scattering

Markus R. Mosbech·Olga Garcia-Gallego·Vid Iršič·Matteo Viel·Julien Lesgourgues
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Abstract

We present new constraints on models of dark matter interacting with neutrino, based on high-resolution Lyman-$\alpha$ forest data. We perform a suite of full hydrodynamical simulations of these models, spanning a range of interaction strengths and thermal histories. We train an emulator on the simulation results. A Monte Carlo Markov Chain analysis yields an upper limit on the interaction strength of $u_{\nu\chi} \leq1.5\times10^{-8}$ (95% C.L.), which is the strongest direct bound to date on such interactions. Our results exclude previous hints of non-zero interactions presented in the literature. We furthermore compare our results to those obtained by mapping warm dark matter constraints to other models with suppressed small-scale structure, and find that these methods would overestimate the constraining power for this model.

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Markus R. Mosbech, Olga Garcia-Gallego, Vid Iršič, Matteo Viel, Julien Lesgourgues. 2026-07-16. High resolution Lyman-{\alpha} forest constraints on dark matter-neutrino scattering. https://arxiv.org/abs/2607.15020

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