{"paper":{"title":"A 78 Day X-ray Period Detected from NGC 5907 ULX1 by Swift","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.HE","authors_text":"A. C. Fabian, D. Barret, D. J. Walton, D. Stern, F. A. Harrison, F. Fuerst, L. Tao, M. Bachetti, M. Brightman, M. Heida, M. J. Middleton, N. Gehrels, N. Webb, T. P. Roberts, V. Rana","submitted_at":"2016-07-25T20:00:05Z","abstract_excerpt":"We report the detection of a $78.1\\pm0.5$ day period in the X-ray lightcurve of the extreme ultraluminous X-ray source NGC 5907 ULX1 ($L_{\\rm{X,peak}}\\sim5\\times10^{40}$ erg s$^{-1}$), discovered during an extensive monitoring program with Swift. These periodic variations are strong, with the observed flux changing by a factor of $\\sim$3-4 between the peaks and the troughs of the cycle; our simulations suggest that the observed periodicity is detected comfortably in excess of 3$\\sigma$ significance. We discuss possible origins for this X-ray period, but conclude that at the current time we can"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1607.07448","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"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"}