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arXiv · 1105.4721

Drastic Spectroscopic Variability of the Be/X-ray Binary A0535+262/V725 Tau during and after the 2009 Giant Outburst

Yuuki Moritani·Daisaku Nogami·Atsuo T. Okazaki·Akira Imada·Eiji Kambe·Satoshi Honda·Osamu Hashimoto·Kohei Ichikawa
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Abstract

We report on high-dispersion optical spectroscopic observations of the Be/X-ray binary A0535+262/V725 Tau during the giant outburst in November/December 2009 and after it. The observed emission line profiles, reflecting the structure of the geometrically thin circumstellar envelope of the Be star (Be disk), show drastic variabilities and indicate the existence of a warped component. The enhanced blue shoulder seen after periastron passage implies the gas stream from a dense part of the Be disk to the neutron star.

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Yuuki Moritani, Daisaku Nogami, Atsuo T. Okazaki, Akira Imada, Eiji Kambe, Satoshi Honda, Osamu Hashimoto, Kohei Ichikawa. 2011-05-24. Drastic Spectroscopic Variability of the Be/X-ray Binary A0535+262/V725 Tau during and after the 2009 Giant Outburst. https://doi.org/10.1093/pasj%2F63.4.l25

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