{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"8d92659b622b7994eaec311070898eaf7299db39aff4841174aef594b852e92d","created":"2026-10-03T07:18:08Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"2b6e939a1d9bdf199fa4d6f60a53c3542178f96c4b74c4764c2bfe76bbbd3c3c","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"plasma.edge-pedestal-elms.elm-free-reactor-regime","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"Several tokamak operating modes keep good confinement without large ELM bursts, but each has been found only under conditions that a reactor may not reach. Whether any of them survives at reactor density, low rotation and a cool divertor is unknown.","posed_since":"","precise":"Candidate regimes are QH-mode (edge harmonic oscillation), I-mode, EDA H-mode, small or grassy ELM regimes (quasi-continuous exhaust) and negative-triangularity L-mode edges. Determine whether at least one achieves $H_{98}$ near 1, no type-I ELMs and a detached divertor simultaneously at reactor-relevant $n_{e}/n_{G}$ of about 0.8 or more, low external torque, high separatrix density and pedestal collisionality as low as ITER $Q = 10$. An answer is a demonstrated discharge meeting all conditions on one device, or a validated stability analysis showing that each regime's access window excludes them.","problem_ref":null,"references":"","settled_by":"A steady discharge meeting all listed conditions simultaneously, together with a validated model of its access window extrapolated to ITER.","status_note":"","title":"Is any ELM-free or small-ELM regime compatible with reactor conditions","topic_ref":"037681ebe2f068d361e19b0b90c7ad8b9281d3aee6de68370b6a285f803d9ac9"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"20533b0e83e6778a8547a5f7ebb3b815e42e6969f80fff7e3f6449d666011b2b","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"45442612aa3e7d1accb2fbe57cc9820e6c645216ad60f8af09d9da76e1597829","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"9EA17nKN16jln9z9LPAELtzuHXxoWrnO3aFDJ6DS2O59Azs0TUyksxhkak3npaXumsXIk9M_0JzZakk2IAl6CA"},"schema":"pubphys.envelope/1"},"record_hash":"20533b0e83e6778a8547a5f7ebb3b815e42e6969f80fff7e3f6449d666011b2b","leaf_index":1832}