{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"6f63a48200efcae7f7b490a1820af6082432808e9dfe9eb3080fb216de4c773b","created":"2026-10-03T07:17:54Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"75c14346cc94bf6896596271c27911aa174added67e348e0f778ae99bb6a6831","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.circumgalactic-medium.missing-galactic-baryons","kind":"well-posed","literature_status":"partially-resolved","n":"1","parents":[],"plain":"A galaxy like ours should contain about one sixth of its total mass as ordinary matter, but stars and disk gas account for only a fraction of that. The rest may be in hot halo gas or may have been blown out of the halo.","posed_since":"","precise":"For halos of $M_h \\sim 1e12\\,M_{\\mathrm{sun}}$, stars and interstellar gas account for roughly 20 to 30 percent of $f_b M_h$ ($f_b \\sim 0.16$, the cosmic baryon fraction). Determine the mass in each phase of halo gas (cool $1e4\\,\\mathrm{K}$, warm $1e5\\,\\mathrm{K}$, hot above $1e6\\,\\mathrm{K}$) inside the virial radius and the mass ejected beyond it.","problem_ref":null,"references":"","settled_by":"Combined X-ray emission, Sunyaev-Zeldovich and fast-radio-burst dispersion measurements of the gas profile around a stacked sample of Milky Way-mass galaxies out to and beyond the virial radius.","status_note":"eROSITA stacking detects extended hot gas around Milky Way-mass galaxies, but its share of the budget remains debated (Zhang et al., A&A, 2026).","title":"Where are the missing baryons of Milky Way-mass galaxies?","topic_ref":"0def120d1b6025e505d1b17c3590b27372b9f92290b62b2df74ed8a1826b48cb"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"c9afa47442d877a07e3068c4cdf423a748b2f71fa9d516f7d0e6b95d5af9b248","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"6d526469a242cc05cd3daf292cb0ee2c57a551553e52208eea59f47ff32fb895","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"oaDr9OHYgR9TXGZc1-RIeoVeuGhJLnmfjsxJm5nPVMsQRS-BzlmUOZ9LlHeqjvxreF3Vhcv8N42dofQrYLu_CQ"},"schema":"pubphys.envelope/1"},"record_hash":"c9afa47442d877a07e3068c4cdf423a748b2f71fa9d516f7d0e6b95d5af9b248","leaf_index":492}