Abstract
Brγ and He I 2.058 μm images of the Galactic center reveal that most of the Brγ emission is associated with interstellar gas but that the He I is largely concentrated on individual, luminous stars that therefore must be hot. High-resolution spectra of these stars, emphasizing He I 2.058 μm through Brγ 2.166 μm, are compared with spectra of 98 hot, luminous stars from the literature and new spectra of 43 luminous galactic emission-line stars including late nitrogen sequence Wolf-Rayet, luminous blue variable (LBV), Oe, Of, and ON supergiant stars. Combining our data with other observations from the literature, the He I sources in the central parsec include approximately five Ofpe/WN stars and one late-WC star. The inferred luminosity and detection of Mg II emission lines in the spectrum of IRS 16NE make it a likely LBV candidate. However, we find six stars with line widths < 500 km s-1 which defy easy classification, even from the extensive library of comparison spectra we have compiled. Considering the ultraviolet constraints of Serabyn & Lacy and Shields & Ferland and the large number of peculiar hot stars, either we see this stellar population at a very distinctive moment in its evolution, or the conditions of formation or the evolution of the stars must be significantly altered by the environment in the central parsec.
Original language | English (US) |
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Pages (from-to) | 206-216 |
Number of pages | 11 |
Journal | Astrophysical Journal |
Volume | 456 |
Issue number | 1 PART I |
DOIs | |
State | Published - Jan 1 1996 |
Keywords
- Galaxy: Center
- Infrared: Stars
- Stars: Emission-line, be
- Stars: Wolf-rayet supergiants
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science