{"paper":{"title":"Sub-milliarcsecond Optical Interferometry of the HMXB BP Cru with VLTI/GRAVITY","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"astro-ph.SR","authors_text":"A. Amorin, A. Buron, A. Eckart, A. M\\'erand, A. Ram\\'irez, C. Deen, C. Rau, C. Straubmeier, E. Gendron, E. M\\\"uller, E. Sturm, E. Wieprecht, E. Wiezorrek, F. Delplancke-Str\\\"obele, F. Eisenhauer, F. Haussmann, F. Vincent, G. Duvert, G. Finger, G. Perrin, GRAVITY Collaboration: I. Waisberg, G. Rousset, H. Bonnet, I. Wank, J.-B. Le Bouquin, J. Dexter, J. Panduro, J.P. Berger, J. Ramos, J. Sanchez-Bermudez, J. Woillez, K. Perraut, L. Jochum, L. Jocou, L. Pallanca, M. Haug, M. Horrobin, M. Kulas, M. Lippa, M. Sch\\\"oller, M. Wiest, M. Wittkowski, N. Anugu, N. Blind, O. Pfuhl, P. F\\'edou, P. Garcia, P. Kervella, P. L\\`ena, R. Abuter, R. Dembet, R. Garcia Lopez, R. Genzel, R.-R. Rohloff, S. Gillessen, S. Hippler, S. Lacour, S. Rabien, S. Scheithauer, S. Yazici, Th. Henning, T. Ott, T. Paumard, V. Lapeyr\\`ere, W. Brandner, W. de Wit, X. Haubois, Y. Cl\\'enet, Y. Kok, Z. Hubert","submitted_at":"2017-05-05T18:07:18Z","abstract_excerpt":"We observe the HMXB BP Cru using interferometry in the near-infrared K band with VLTI/GRAVITY. Continuum visibilities are at most partially resolved, consistent with the predicted size of the hypergiant. Differential visibility amplitude ($\\Delta |V| \\sim 5\\%$) and phase ($\\Delta \\phi \\sim 2 \\deg$) signatures are observed across the HeI $2.059 \\mu$m and Br$\\gamma$ lines, the latter seen strongly in emission, unusual for the donor star's spectral type. For a baseline $B \\sim 100$m, the differential phase RMS $\\sim 0.2 \\deg$ corresponds to an astrometric precision of $\\sim 2 \\mu$as. A model-inde"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1705.02351","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/1705.02351/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"}