{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"388623de254eb157e91f5623dc6d87c25ad71f0d14b993c7a2a34aec395604a4","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["20533b0e83e6778a8547a5f7ebb3b815e42e6969f80fff7e3f6449d666011b2b","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"15ad0ba08b6788425a3eb31db0c325a2aa5d83369d7199674894d2b26a7732a8","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":"2","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":"20533b0e83e6778a8547a5f7ebb3b815e42e6969f80fff7e3f6449d666011b2b","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":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"3eee2ff493f97da1ff663ed6abb5f34f2e7bdc3b775a7cb508793a2c83be5a89","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f5635a39c26b87b482fd19340bfd75682d4d1550cedd31d7302f12d8e35b3279","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"RPwdXEO6IAMwCjnRdDWTt52nAdDN2sIUnwBZGwPjCZrVDMRadMbcAa9gA5k2A0PFf14ZHBacU3Q8Vi0BUMDDCg"},"schema":"pubphys.envelope/1"},"record_hash":"3eee2ff493f97da1ff663ed6abb5f34f2e7bdc3b775a7cb508793a2c83be5a89","leaf_index":3566}