PI: Guy Stringfellow, University of Colorado, Guy.Stringfellow@colorado.edu
Address: Center for Astrophysics and Space Astronomy, 389 UCB, Boulder, CO 80309-0389, USA
CoI: Vasilii Gvaramadze, Sternberg Astronomical Institute, Russia
Title: Confirming LBV Candidates Through Variability: A Photometric and Spectroscopic Monitoring Study
Abstract: Luminous Blue Variable (LBV) stars represent an extremely rare class of luminous massive stars with high mass loss rates. The paucity (~12) of confirmed Galactic LBV precludes determining a solid evolutionary connection between LBV and other intermediate (e.g. Ofpe/WN9, WNL) phases in the life of very massive stars. We’ve been conducting an optical/near-IR spectral survey of a large subset of central stars residing within newly discovered \it Spitzer nebulae and have identified over two dozen new candidate LBVs (cLBVs) based on spectral similarity alone; confirming them as bona fide LBVs requires demonstrating 1-3 mag photometric and spectroscopic variability. This marks a significant advancement in the study of massive stars, far outweighing the return from many studies searching for LBVs and WRs the past several decades. Monitoring from semesters 2011B-2012A already has confirmed one new cLBV as a bona fide LBV. We propose to continue optical-IR photometric monitoring of these cLBVS with the 1.3m. Chiron, replacing the RC spectrograph on the 1.5m, now allows high-resolution optical spectroscopic monitoring of bright cLBVs, 11 of which are proposed herein. Spectra are important for understanding the physics driving photometric variability, properties of the wind, and allow analysis of line profiles.
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