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J.P. Simpson (NASA/ARC), A.S. Cotera, A. Leistra (UAz)
W49A is one of the most luminous H II regions in the Galaxy; it consists of numerous ultracompact H II regions plus additional sources containing lower density ionized gas. As part of a long term project to identify the obscured hot luminous stars of the Galaxy (see e.g., Leistra, Cotera, and Simpson, this meeting), in May and June, 2000, we imaged W49A at H and K with the Bok 2.3 m telescope of Steward Observatory and took 2.0-2.2 \micron\ spectra of those regions exhibiting diffuse emission at K. The areas searched were the W49A components South, CC, and the diffuse radio emitting gas just East of the ultracompact components of W49A North (see De Pree, Mehringer, and Goss 1997 for nomenclature); the ultracompact components are not visible at K, no doubt because of the deep extinction of the molecular cloud in which they are imbedded. The telescope was stepped through the 3 positions at 1.5'' intervals; R~1000 long-slit spectra were taken at each position with the goal of identifying hot stars by their HeI and Br\gamma emission lines. On a later night, longer integration time spectra were taken in H and K-band of each candidate emission line star. Three stars are confirmed to contain emission lines in their spectra. One of the stars is in W49 South and the other two are in the diffuse region in the vicinity of radio components O2, O3, and JJ. We will discuss the classification further and the contributions of these stars to the ionizing flux needed for their locations in the H II region.