{"paper":{"title":"X-ray variability of SDSS J000532.84+200717.4: from a normal state to an X-weak state","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"astro-ph.GA","authors_text":"Chichuan Jin, Fukun Liu, Jinhong Chen, Liming Dou, Ning Jiang, Tinggui Wang, Wenfeng Wen, Xiaohui Yang, Xu Zhang, Yanli Ai, Yuming Fu","submitted_at":"2026-04-01T04:38:46Z","abstract_excerpt":"We present a multi-epoch study of the extreme X-ray variability of the type~1 quasar SDSS~J000532.84+200717.4 using archival observations from \\textit{XMM-Newton}, \\textit{Swift}/XRT, \\textit{EP-FXT}, and \\textit{ROSAT}, together with new optical spectroscopy and multi-wavelength photometry. The 0.2--10~keV X-ray flux exhibits a transition from a high state to a subsequent low state, declining by more than an order of magnitude and placing the source in the X-ray--weak regime ($\\Delta\\alpha_{\\rm ox} \\lesssim -0.3$). Significant variability on timescales of days to weeks persists within the low"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2604.00476","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.00476/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}