{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"4351e6ecd48a7a2346b91a1d59c12d83c52e7e366c950e083828262912d03573","created":"2026-10-03T07:17:56Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011","e76cc77c10d372ad4ec2ffe6c3b98ce6c9c4fc95e87ae1f41e4baa319e9d3499"],"salt":"822fceefc7e4e0f9a2acbc30361d90f519f0df607d2b1bfce12024bc56c91bf7","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"beams.srf-q-slope.anti-q-frequency","kind":"phenomenon","literature_status":"open","n":"1","parents":[{"note":"Frequency and mean-free-path boundary is a sharper part of anti-Q-slope origin","parent_revision":"e76cc77c10d372ad4ec2ffe6c3b98ce6c9c4fc95e87ae1f41e4baa319e9d3499","relation":"special_case"}],"plain":"The loss reduction with field is strong in some cavities and absent in others, and depends on the cavity frequency and temperature. A theory must explain where it appears and where it does not.","posed_since":"","precise":"Measurements show the anti-Q-slope is pronounced at $f \\ge 1.3\\,\\mathrm{GHz}$ and weak or absent at lower frequency, and depends on $T$ and on the electron mean free path set by doping. Derive the boundary in $(f,T,\\text{mean free path})$ separating field-decreasing from field-increasing $R_{\\mathrm{BCS}}$.","problem_ref":null,"references":"","settled_by":"A predicted crossover map confirmed by cavities of several frequencies prepared with identical surface treatment.","status_note":"","title":"Frequency and temperature dependence of the anti-Q-slope","topic_ref":"07f4b938cd1bb3f7a5e87f7eeb09fc5d6d7083a2a323fd1976ce3e976aa2af82"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"d6a013d519e9169e0ceabf373a3848d9feac5868eefde01564fc72f8047b5c2c","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"64cc28d95ed27d6f0343010b995bcbe82e2607f6a85ae450a93b4b4bda870a17","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"W87XkvBHrj691Rf9yKgo0NrpSyc9dH5EQcOnGd0QyV9eiQ4PV2qTmZLy4XPzGJtHg7HxSTQz9dzsM82Vo10RBA"},"schema":"pubphys.envelope/1"},"record_hash":"d6a013d519e9169e0ceabf373a3848d9feac5868eefde01564fc72f8047b5c2c","leaf_index":709}