{"paper":{"title":"TW Hya: Spectral Variability, X-Rays, and Accretion Diagnostics","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"2), 3), (3) Astronomy Dept., (4) Australian National Observatory, (5) Institute of Astronomy, (6) South African Astronomi cal Observatory, (7) University of New South Wales, (8) Indian Institute of Ast rophsics, (8) S. C. Schuler ((1) Harvard-Smithsonian Center for Astrophysics, (9) National Optical Astronomy Observatory, A. Bonanos (5), ACT, A. K. Dupree (1), Arg entina, Astrophysics, Athens, Australia, AZ, AZ), Bangalore, Buenos Aires, Cambridge, Canberra, E. E. Schneider (1, G. J. M. Luna (1, Greece, India, L. A. Crause (6), MA (2) Instituto de Astronomia y Fisica del Espacio, Mount Stromlo Observatory, M. S. Bessell (4), National Observatory of Athens, N. S. Brickhouse (1), Observatory, South Africa, S. R. Cranmer (1), S. V. Mallik, Tucson, University of Arizona, W. A. Lawson (7)","submitted_at":"2012-02-28T21:05:16Z","abstract_excerpt":"The nearest accreting T Tauri star, TW Hya was observed with spectroscopic and photometric measurements simultaneous with a long se gmented exposure using the CHANDRA satellite. Contemporaneous optical photometry from WASP-S indicates a 4.74 day period was present during this time. Absence of a similar periodicity in the H-alpha flux and the total X-ray flux points to a different source of photometric variations. The H-alpha emission line appears intrinsically broad and symmetric, and both the profile and its variability suggest an origin in the post-shock cooling region. An accretion event, s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1202.6373","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"}