{"paper":{"title":"Chandra imaging spectroscopy of 1E 1740.7 - 2942","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"E. Gallo, R. Fender (University of Amsterdam)","submitted_at":"2002-08-15T13:32:44Z","abstract_excerpt":"We have observed the black hole candidate 1E 1740.7 - 2942, the brightest persistent hard X-ray source within a few degrees of the Galactic centre, for 10 ksec with Chandra (ACIS-I) on August 2000. Attempting to compensate for pile-up effects we found the spectra were well-fit by an absorbed power law, with photon indices Gamma = 1.54 ^{+0.42}_{-0.37} (readout streak) and Gamma = 1.42^{+0.14}_{-0.14} (annulus), consistent with a black hole low/hard state. We have analysed a public observation performed by Chandra which utilised short frames in order to avoid severe pile-up effects: subtracting"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0208296","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/astro-ph/0208296/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"}