Abstract

Identification of New Galactic Candidate-LBVs and WR Stars from IR Spectroscopy

Guy Stringfellow (University of Colorado)

V. Gvaramadze (SAI MSU), Y. Beletsky (ESO), A. Kniazev (SAAO)

We have undertaken a near-infrared spectral survey of stars associated with compact shells recently revealed (primarily) by the MIPSGAL (24 micron) and GLIMPSE (8 micron) Spitzer surveys. These (circumstellar) shells are produced by massive evolved stars, and we report on the classification of about 3 dozen new stellar spectra. Through spectral similarity with known LBV and WR stars, a large population of previously unidentified candidate LBVs (cLBVs) and a smaller number of new WR stars have been discovered. This significantly increases the number of Galactic cLBVs previously known only just a few years ago and confirms that nebulae are inherent to most cLBVs. The diversity seen amongst the infrared spectra for cLBVs, including the prevalence and strength of Fe II (and other low-ionization species), He, and H lines and inference on wind properties will be discussed.