Program: GS-2007A-Q-67

Wolf-Rayet (WR) stars are the short-lived, chemically evolved descendants of very massive O stars, and so act as excellent tracers of massive star formation in galaxies. Analysis of their spectrum provides excellent tests for stellar evolutionary models since their surface chemistry evolves with time, reflecting the products of core nucleosynthesis. While the distribution of WR stars in external galaxies of the Local Group is fairly well known, very little is known about their distribution in our own Milky Way, mostly because the most massive stars form very close to the Galactic plane and are therefore hidden by interstellar dust. Our team has recently completed the first systematic large-scale infrared survey for Galactic Wolf-Rayet stars. This proposal aims at obtaining high quality K-band spectra of our faintest, most promising candidates with GNIRS to determine their fundamental parameters. This proposal is intended for less than ideal observing conditions.