{"paper":{"title":"Long term optical variability of bright X-ray point sources in elliptical galaxies","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO","astro-ph.GA"],"primary_cat":"astro-ph.HE","authors_text":"B. R. S. Babu, C. D. Ravikumar, K. Jeena, P. Shalima, R. Misra, V. Jithesh","submitted_at":"2014-04-14T16:31:35Z","abstract_excerpt":"We present long term optical variability studies of bright X-ray sources in four nearby elliptical galaxies with {\\it Chandra} Advanced CCD Imaging Spectrometer array (ACIS-S) and {\\it Hubble Space Telescope (HST)} Advanced Camera for Surveys observations. Out of the 46 bright (X-ray counts $> 60$) sources that are in the common field of view of the {\\it Chandra} and {\\it HST} observations, 34 of them have potential optical counterparts, while the rest of them are optically dark. After taking into account of systematic errors, estimated using the field optical sources as reference, we find tha"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1404.3644","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"}