{"paper":{"title":"An embedded X-ray source shines through the aspherical AT2018cow: revealing the inner workings of the most luminous fast-evolving optical transients","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"A. Hajela, A. MacFadyen, A. V. Kozlova, B. D. Metzger, B. W. Grefenstette, C. Ferrigno, C. Guidorzi, D. Brethauer, D. D. Frederiks, D. G\\\"otz, D. L. Coppejans, D. Milisavljevic, D. Patnaude, D. S. Svinkin, E. Berger, E. Bozzo, E. Kuulkers, E. R. Coughlin, G. Migliori, G. Terreran, I. V. Chilingarian, I. Vurm, J. Banovetz, J. F. Steiner, K. D. Alexander, K. Hurley, K. Paterson, L. Ducci, M. Bietenholz, M. Nicholl, M. R. Drout, N. Bartel, N. Roth, P. K. Blanchard, P. Laurent, P. Ubertini, Raffaella Margutti, R. Cartier, R. Chornock, S. Mereghetti, T. Eftekhari, T. Laskar, V. Savchenko, W. Fong","submitted_at":"2018-10-25T04:46:42Z","abstract_excerpt":"We present the first extensive radio to gamma-ray observations of a fast-rising blue optical transient (FBOT), AT2018cow, over its first ~100 days. AT2018cow rose over a few days to a peak luminosity $L_{pk}\\sim4\\times 10^{44}$ erg/s exceeding those of superluminous supernovae (SNe), before declining as $\\propto t^{-2}$. Initial spectra at $\\lesssim 15$ days were mostly featureless and indicated large expansion velocities v~0.1c and temperatures reaching 30000 K. Later spectra revealed a persistent optically-thick photosphere and the emergence of H and He emission features with v~sim 4000 km/s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1810.10720","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"}