{"paper":{"title":"A long-term optical - X-ray correlation in 4U 1957+11","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"3, 4), Cardiff University (3) Open University (4) University of Glamorgan (5) University of Southampton), D. M. Russell (1), E. Breedt (5), F. Lewis (2, J. S. Clark (3), P. Roche (2, R. P. Fender (5) ((1) University of Amsterdam (2) Faulkes Telescope Project","submitted_at":"2009-11-23T22:09:26Z","abstract_excerpt":"[abridged] Three years of optical monitoring of the low-mass X-ray binary (LMXB) 4U 1957+11 is presented. The source was observed in V, R and i-bands using the Faulkes Telescopes North and South. The light curve is dominated by long-term variations which are correlated (at the > 3 sigma level) with the RXTE ASM soft X-ray flux. The variations span one magnitude in all three filters. We find no evidence for periodicities in our light curves, contrary to a previous short-timescale optical study in which the flux varied on a 9.3-hour sinusoidal period by a smaller amplitude. The optical spectral "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0911.4501","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"}