| タイトル | Ultraviolet Imaging Telescope photometry of massive stars - The OB association NGC 206 in M31 |
| 著者（英） | Stecher, Theodore P.; Isensee, Joan E.; Hill, Jesse K.; Bohlin, Ralph C.; O'Connell, Robert W.; Pfarr, Barbara B.; Roberts, Morton S.; Smith, Andrew M.; Neff, Susan G. |
| 著者所属（英） | NASA Goddard Space Flight Center; NASA Headquarters |
| 発行日 | 1992-08-10 |
| 言語 | eng |
| 内容記述 | The Ultraviolet Imaging Telescope (UIT) obtained UV images of the giant M31 OB association NGC 206. Magnitudes in bands at 1520 and 2490 A were obtained for 30 massive stars, which demonstrate the effectiveness of UIT for photometry of moderately crowded hot stars to V about 21. The UV colors and magnitudes observed for stars in NGC 206 place them in the region of the color magnitude diagram occupied by evolutionary models for 30-60 solar mass stars, after correcting for extinction. The brighter stars are systematically redder than the fainter stars, indicating that they are supergiants of age about 4 Myr, while the fainter, bluer stars are nearer age zero. The relative numbers of probable supergiants measured by us and the number of probable main-sequence O stars measured from optical images are in agreement with the relative lifetimes. Calculated UIT colors are presented for a library of standard star spectra constructed from IUE and ground-based observations. |
| NASA分類 | ASTRONOMY |
| レポートNO | 93A12537 |
| 権利 | Copyright |
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