{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"e30c6d15e3050c8634ad0fca2827d3813cf8dfc0465fdf7d0bfa6fc277616606","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["3cb42522eb6acd43f0f0debf98bbcae131552215be6acdb523466bccb80da689","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"eb4d7862bbd070e0f5273dfaee6019803e8f106f07d3ef685399a202b3b33b9f","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"hep.sterile-neutrino-anomalies.ev-sterile","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"A fourth neutrino that feels no force except gravity, with mass near 1 eV, could explain some anomalies. It would show up as extra appearance and disappearance at short distances.","posed_since":"","precise":"Determine whether a fourth mass state with $\\Delta m^2_{41} \\sim 0.1 \\text{ to } 10\\,\\mathrm{eV}^2$ and mixings |U_e4|, |U_mu4| large enough to produce sin^2(2 theta_mue) $\\sim 10^{-3}$ exists. An answer is a $5\\,\\sigma$ oscillation signal or exclusion of the region preferred by LSND and gallium in both appearance and disappearance.","problem_ref":"3cb42522eb6acd43f0f0debf98bbcae131552215be6acdb523466bccb80da689","references":"","settled_by":"Combined SBN-program oscillation fits with near and far detectors, plus reactor (PROSPECT, STEREO) and atmospheric (IceCube) disappearance limits.","status_note":"Appearance-disappearance tension in global fits and the 2025 MicroBooNE result disfavor the simple 3+1 model.","title":"Does an eV-scale sterile neutrino exist?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"0ab12abbb59c219c05c20692344cd16b2e06a38aac02a9a157e2a13069f998df","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"90b9d29bfc1a9b9bcf5978e60ddab3486f5cc68a7778e6fbda08dfb57e72364b","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"ZvGGGqSLtb5g_kBXTEuLKStDGkbh9hj6muSULO39OlOFy3ymNzbldQ24CVzgffw7ueZ2fH1EXHJKGO7knVptAw"},"schema":"pubphys.envelope/1"},"record_hash":"0ab12abbb59c219c05c20692344cd16b2e06a38aac02a9a157e2a13069f998df","leaf_index":3382}