Paper

{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2603.24331v1</id>\n    <title>Lyman-$α$ Forest Constraint on Dark Matter from Dark Sector Decay</title>\n    <updated>2026-03-25T14:10:59Z</updated>\n    <link href='https://arxiv.org/abs/2603.24331v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2603.24331v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>By exploiting small-scale structure formation probed by Lyman-$α$ forest observations, we study constraints on a model of dark matter from dark sector decay. We compute the phase space distribution of the dark matter and the linear matter power spectrum. We map the non-thermal dark matter distribution in this dark matter model to an approximate thermal warm dark matter distribution, and use this approximation to obtain a constraint from the Lyman-$α$ forest observation. We combine the latest Lyman-$α$ forest bounds with the constraint from the Big Bang Nucleosynthesis. As these two probes offer highly complementary constraints, we impose strong limits on sub-GeV dark matter. Consequently, masses lighter than $\\sim 10^{-1}$ GeV are excluded, thereby significantly limiting the allowed parameter space. More broadly, our findings demonstrate the utility of small-scale structure observations in testing non-thermal dark matter paradigms, offering valuable insights for exploring a wider class of late-time decay models.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='hep-ph'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='astro-ph.CO'/>\n    <published>2026-03-25T14:10:59Z</published>\n    <arxiv:comment>23 pages, 14 figures</arxiv:comment>\n    <arxiv:primary_category term='hep-ph'/>\n    <author>\n      <name>Si-Yuan Zhao</name>\n    </author>\n    <author>\n      <name>Yi-Cheng Dai</name>\n    </author>\n    <author>\n      <name>Wei Liao</name>\n    </author>\n    <author>\n      <name>Yi-Song Lu</name>\n    </author>\n  </entry>"
}