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.
@article{arxiv.1408.6232,
title = {Discovery of a new Galactic bona fide luminous blue variable with Spitzer},
author = {V. V. Gvaramadze and A. Y. Kniazev and L. N. Berdnikov and N. Langer and E. K. Grebel and J. M. Bestenlehner},
journal= {arXiv preprint arXiv:1408.6232},
year = {2015}
}
Comments
5 pages, 3 figures, accepted for publication in MNRAS Letters