{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"bf66eb62cdcc508b658c7a781359f98c75017dcb947c56469828133b4840af59","created":"2026-10-03T07:17:56Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"d1b049f007da8696c1f7565d432c91d938c9f1d75d11820a8459dea08515b542","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"beams.csr-microbunching.ssmb-euv-source","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"If electrons in a storage ring stayed bunched into slices a few nanometers long on every turn, they would emit strong coherent ultraviolet light continuously; only the first step of this scheme has been shown.","posed_since":"2010","precise":"Steady-state microbunching (SSMB) uses laser modulators for longitudinal focusing in a low-momentum-compaction ring so that electrons stay in optical-scale microbunches turn after turn; retention of laser-induced microbunching at a $1.064e-4\\,\\mathrm{cm}$ wavelength over successive turns was reported at the Metrology Light Source, Berlin, in 2021 (Deng et al., https://doi.org/10.1038/s41586-021-03203-0). Determine whether a ring can hold microbunches of rms length below $\\sim 2e-7\\,\\mathrm{cm}$ in steady state, with quantum excitation, intrabeam scattering and laser phase noise included, giving coherent radiation at $1.35e-6\\,\\mathrm{cm}$ ($13.5\\,\\mathrm{nm}$) with average power near $1e10\\,\\mathrm{erg}/\\mathrm{s}$.","problem_ref":null,"references":"","settled_by":"Measured steady-state coherent emission at the target wavelength whose power scales as the square of the number of electrons per microbunch.","status_note":"INSPIRE records through 2026 show proof-of-principle work at the Metrology Light Source and ring design studies, with no steady-state operation reported.","title":"Steady-state microbunching in a storage ring at EUV wavelengths","topic_ref":"5a86adf3ddd836ff2ccead3d8facd2c7c42ba046664278d11978618137dcefd5"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"d98cdaca290ac28b7ec854d5f47a9125d9fb4085c8bcc8ee300dc91c2ef4c18d","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"0ee29e228ac137461988680640680b915fc06d2858ff50d1dedcf53214f46210","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"Rob02H0cUTwO5sqGvqKnOJOxLyK0Afqgf1cvQ1nX3JDJeOHPWdTk7RzMWJ36mBM4fkbjHnhUwtEPnVpb41_TDw"},"schema":"pubphys.envelope/1"},"record_hash":"d98cdaca290ac28b7ec854d5f47a9125d9fb4085c8bcc8ee300dc91c2ef4c18d","leaf_index":663}