{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"3e0b4bbfbf7e74f57778536c76689a262bea4fb2ebb232c48b9cbe6b376c5852","created":"2026-10-03T07:17:55Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"29ef2b84fba71e61aa59863bfeabf08f15d1294910d4178b4295a4c880470fd7","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"astro.stellar-mixing.overshoot-mixing-length","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Stellar models describe convection, the boiling motion of hot gas, with a single adjustable length and add extra mixing past the convective boundary by hand. Different calibrations disagree, and the chosen values change derived stellar ages.","posed_since":"","precise":"Mixing-length theory uses $\\alpha_{\\mathrm{MLT}}\\sim 1.8$ calibrated on the Sun, and convective boundary mixing uses an overshoot extent of about 0.1 to 0.3 pressure scale heights. Determine whether $\\alpha_{\\mathrm{MLT}}$ is universal across mass, metallicity and evolutionary stage, and determine the overshoot extent and profile as a function of stellar mass, from 3D simulations validated against eclipsing binaries and asteroseismology.","problem_ref":null,"references":"","settled_by":"3D convection simulations at realistic stellar parameters yielding a boundary-mixing law that fits eclipsing-binary and asteroseismic constraints across 1 to 10 $M_{\\mathrm{sun}}$.","status_note":"Eclipsing-binary calibrations suggesting overshoot grows with mass have been disputed as a degeneracy with other model parameters.","title":"Physical calibration of convective overshoot and the mixing length","topic_ref":"b73961901a806edc363634c4122737e7e1c2d5e71cea37c534e23f436adf3480"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"f50d91a146526adcbaf5fc66bd551899a5bb803ff22e5210bf277607ce32277f","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"cac9ef7422b5dd61d37c58ec07c1249550c913d304158a5250851a0b9a7f24b2","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"XQhvfyzyurFpTpwpL7fAPGxCMPrW1MZWNujzrwdVjbkiP1R2vYfRsKTEWkA281skqLLifIxeYpokatJ3b-02Dg"},"schema":"pubphys.envelope/1"},"record_hash":"f50d91a146526adcbaf5fc66bd551899a5bb803ff22e5210bf277607ce32277f","leaf_index":630}