{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/strong-constraints-on-decay-and-annihilation","title":"Strong constraints on decay and annihilation of dark matter from heating of gas-rich dwarf galaxies","arxiv_id":"2111.08025","date":"2021-11-15","proceeding":null,"authors":["Digvijay Wadekar","Zihui Wang"],"abstract":"Gas-rich dwarf galaxies located outside the virial radius of their host are relatively pristine systems and have ultra-low gas cooling rates. This makes them very sensitive to heat injection by annihilation or decay of dark matter (DM). Such dwarfs are particularly sensitive to DM producing e$^\\pm$ with energies 1$-$100 MeV or photons with energies 13.6 eV$-1$ keV, because these products can be efficiently thermalized in the neutral hydrogen gas of the dwarfs. Following the methodology of Wadekar and Farrar (2021), we require the rate of heat injection by DM to not exceed the ultra-low radiative cooling rate of gas in the Leo T dwarf galaxy. This gives model-independent bounds on $(i)$ the decay lifetime of DM to $e^\\pm$ (photons) which are stronger than all the previous literature for $m_\\mathrm{DM}\\sim$ 1$-$10 MeV ($m_\\mathrm{DM}\\sim0.02-1$ keV), $(ii)$ annihilation of DM to $e^{\\pm}$ comparable to constraints from CMB and X/$\\gamma$-ray surveys. We also translate our bounds for the case of the following DM models: axion-like particles (ALPs), sterile neutrinos, excited DM states, higgs portal scalars and dark baryons. Observations of gas-rich low-mass dwarfs from upcoming 21cm and optical surveys can therefore be powerful probes of a multitude of models of DM.","url_abs":"https://arxiv.org/abs/2111.08025v2","url_pdf":"https://arxiv.org/pdf/2111.08025v2.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"strong-constraints-on-decay-and-annihilation","repo_url":"https://github.com/JayWadekar/Gas_rich_dwarfs","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}