{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"f831c1f1d10f0422bc1b949e905881de0898557ec3c31b5bbd5ce7fe904dee25","created":"2026-10-03T07:18:02Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"5ef88b0e8155ffcc65b6aa33b4d88e9f58f4b6b69b1c73849be860bfed6ac1fc","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"earth.atmospheric-electricity.tgf-mechanism","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Thunderstorms emit flashes of gamma rays lasting less than a thousandth of a second, made by electrons pushed near light speed. Whether these electrons come from the lightning tip or from a self-sustaining avalanche in the cloud field is disputed.","posed_since":"1994","precise":"Terrestrial gamma-ray flashes are sub-millisecond bursts with photon energies up to tens of MeV produced by relativistic runaway electron avalanches. Distinguish relativistic feedback discharge (avalanches sustained by backward positrons and photons in the large-scale field) from thermal runaway of electrons at lightning leader tips followed by avalanche amplification. An answer is a model matching TGF fluence, spectra, durations and timing relative to radio leader steps.","problem_ref":null,"references":"","settled_by":"Coincident space or ground gamma detection with microsecond radio mapping of the associated leader.","status_note":"Downward TGFs at ground arrays (e.g. Pierre Auger, arXiv:2507.15669, 2025) add constraints; both mechanisms remain in contention.","title":"What produces terrestrial gamma-ray flashes?","topic_ref":"065176f8516fade9b4b12b58d43d1b3de469d91e84225f18e938ff61f04b285e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"0471d0079ec5f3dc6e10538c7d2d25aa4e4e558aa0956cf9c277b58afaba0532","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"c9e2d35971a41aafc2a7d71029fc879556ad03cb2a31f3e0a2a3bfc73de2d336","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"9xyBhlTl01oKzoY_d4M0U1Pbqb7c-S1PetG3DLgmD95Aval4VdNaVwMK6EZxdxGnRjRnioG3AxjZVizZkl3iDQ"},"schema":"pubphys.envelope/1"},"record_hash":"0471d0079ec5f3dc6e10538c7d2d25aa4e4e558aa0956cf9c277b58afaba0532","leaf_index":1294}