{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T02:19:24Z","timestamp":1773368364750,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,31]],"date-time":"2021-01-31T00:00:00Z","timestamp":1612051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000015","name":"U.S. Department of Energy","doi-asserted-by":"publisher","award":["DE-AC02-76SF00515"],"award-info":[{"award-number":["DE-AC02-76SF00515"]}],"id":[{"id":"10.13039\/100000015","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>We discuss the implementation of a suite of virtual diagnostics at the FACET-II facility currently under commissioning at SLAC National Accelerator Laboratory. The diagnostics will be used for the prediction of the longitudinal phase space along the linac, spectral reconstruction of the bunch profile, and non-destructive inference of transverse beam quality (emittance) while using edge radiation at the injector dogleg and bunch compressor locations. These measurements will be folded into adaptive feedbacks and Machine Learning (ML)-based reinforcement learning controls to improve the stability and optimize the performance of the machine for different experimental configurations. In this paper we describe each of these diagnostics with expected measurement results that are based on simulation data and discuss progress towards implementation in regular operations.<\/jats:p>","DOI":"10.3390\/info12020061","type":"journal-article","created":{"date-parts":[[2021,1,31]],"date-time":"2021-01-31T04:53:00Z","timestamp":1612068780000},"page":"61","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Virtual Diagnostic Suite for Electron Beam Prediction and Control at FACET-II"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4719-1831","authenticated-orcid":false,"given":"Claudio","family":"Emma","sequence":"first","affiliation":[{"name":"SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA"}]},{"given":"Auralee","family":"Edelen","sequence":"additional","affiliation":[{"name":"SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9276-0063","authenticated-orcid":false,"given":"Adi","family":"Hanuka","sequence":"additional","affiliation":[{"name":"SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA"}]},{"given":"Brendan","family":"O\u2019Shea","sequence":"additional","affiliation":[{"name":"SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3203-0963","authenticated-orcid":false,"given":"Alexander","family":"Scheinker","sequence":"additional","affiliation":[{"name":"Los Alamos National Laboratory, Los Alamos, NM 87545, USA"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101301","DOI":"10.1103\/PhysRevAccelBeams.22.101301","article-title":"FACET-II facility for advanced accelerator experimental tests","volume":"22","author":"Yakimenko","year":"2019","journal-title":"Phys. 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