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arXiv · 1408.6232

Discovery of a new Galactic bona fide luminous blue variable with Spitzer

V. V. Gvaramadze·A. Y. Kniazev·L. N. Berdnikov·N. Langer·E. K. Grebel·J. M. Bestenlehner
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Abstract

We report the discovery of a circular mid-infrared shell around the emission-line star Wray 16-137 using archival data of the Spitzer Space Telescope. Follow-up optical spectroscopy of Wray 16-137 with the Southern African Large Telescope revealed a rich emission spectrum typical of the classical luminous blue variables (LBVs) like P Cygni. Subsequent spectroscopic and photometric observations showed drastic changes in the spectrum and brightness during the last three years, meaning that Wray 16-137 currently undergoes an S Dor-like outburst. Namely, we found that the star has brightened by \approx 1 mag in the V and I_c bands, while its spectrum became dominated by Fe ii lines. Taken together, our observations unambiguously show that Wray 16-137 is a new member of the family of Galactic bona fide LBVs.

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V. V. Gvaramadze, A. Y. Kniazev, L. N. Berdnikov, N. Langer, E. K. Grebel, J. M. Bestenlehner. 2014-08-26. Discovery of a new Galactic bona fide luminous blue variable with Spitzer. https://doi.org/10.1093/mnrasl/slu141

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