{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"cabb0986ee814d93369fd920ed78fbaedb47f3695a2ed7d1dc4e73b3b30e5c84","created":"2026-10-03T07:17:56Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"217d851e9e1e65b97bade41270c6d517b00611a32d244de68e46e2c02e3360d5","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"beams.microbunching-fel.transform-limited","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The best possible laser pulse has the narrowest color range allowed by its duration. Whether hard X-ray lasers can reach that limit shot after shot is open.","posed_since":"","precise":"Determine whether a seeded or cavity-based XFEL at photon energy $> 5\\ \\mathrm{keV}$ can deliver pulses with time-bandwidth product within 1.5 times the transform limit and pulse-to-pulse energy fluctuation below a few percent, given shot noise and microbunching in the electron beam.","problem_ref":null,"references":"","settled_by":"Single-shot spectral and temporal measurements of a hard X-ray FEL meeting the stated criteria over many shots.","status_note":"","title":"Can XFELs produce stable transform-limited hard X-ray pulses","topic_ref":"96829e4a8214c58e8270f023e22cde3715fc0dd6fc4307b667881195ee4a7930"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"ddbcf58dba29987b52040846a8919e7d28820e1dd68c04906a50239e4f63fa1e","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f1ec6960ca7441c84e414356cbfdc473b690898a6fb7163451c6ea5df36322ce","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"dxUUlWL0S4ldwDd4ukylrJIXXp16zJT6KMvOxDoxn-dds0kKSOzFqAkFXz_mUdGPXhAsOtMHKBRYUBdqy32uAA"},"schema":"pubphys.envelope/1"},"record_hash":"ddbcf58dba29987b52040846a8919e7d28820e1dd68c04906a50239e4f63fa1e","leaf_index":672}