{"paper":{"title":"Spectral Transition and Torque Reversal in X-ray Pulsar 4U 1626-67","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Ethan T. Vishniac, Insu Yi","submitted_at":"1999-05-17T17:19:15Z","abstract_excerpt":"The accretion-powered, X-ray pulsar 4U 1626-67 has recently shown an abrupt torque reversal accompanied by a dramatic spectral transition and a relatively small luminosity change. The time-averaged X-ray spectrum during spin-down is considerably harder than during spin-up. The observed torque reversal can be explained by an accretion flow transition triggered by a gradual change in the mass accretion rate. The sudden transition to spin-down is caused by a change in the accretion flow rotation from Keplerian to sub-Keplerian. 4U 1626-67 is estimated to be near spin equilibrium with a mass accre"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9905214","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/9905214/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"}