{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"98b73294b1a01ab55cea3defa37334bd25aff6ea81a8b58279f908691be3b72b","created":"2026-10-03T07:17:50Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"7b1d1611a86cf52d111d1c92dce15f995d1d05e0fa930bb5ab3f3194175094f5","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"beams.microbunching-fel","field":"beams","n":"1","review_cite":"C. Pellegrini, A. Marinelli, S. Reiche, The physics of x-ray free-electron lasers, Reviews of Modern Physics, 2016","review_link":"https://doi.org/10.1103/RevModPhys.88.015006","review_verified":"true","summary":"In X-ray lasers the electron bunch is compressed to boost its current, but tiny density ripples grow during compression and spoil the beam. The X-ray pulses also start from random noise, so their colors are messy and making them clean is still hard.","title":"Microbunching instability and XFEL longitudinal coherence","topic_ref":null,"why":"These effects limit the spectral purity, brightness and stability of X-ray free-electron lasers."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"96829e4a8214c58e8270f023e22cde3715fc0dd6fc4307b667881195ee4a7930","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"4e630663b40ed3ac78b7afeb43b7d9c3473f2d976526bc398337f154f057e14f","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"iOUEq-S6x6w1b8wYhz7zFKsd2xpdOwvPONOjAuPkryE3Dn3Sf30QDjD0eB16hJRa6Km1pZ1FHh0l55ZLND1VCA"},"schema":"pubphys.envelope/1"},"record_hash":"96829e4a8214c58e8270f023e22cde3715fc0dd6fc4307b667881195ee4a7930","leaf_index":67}