The complex structure of the Si IV 1393.755, 1402.77 °A regions of 68 Be-type stars
Abstract
DACs and SACs phenomena in Si IV resonance lines of 68 Be stars. In our study we apply the method proposed by Danezis et al. (2003) on the spectra of 68 Be stars, taken with I.U.E. and we examine the variations of the physical parameters, stated below, as a function of the spectral subtype. We found that the absorption atmospherical regions where the Si IV resonance lines originated may be formed of one to five independent density layers of matter which rotate with different velocities, producing one to five Satellite Absorption Components (SACs or DACs). With the above method we calculate the values of the apparent rotational and radial velocities, as well as the optical depth of the independent regions of matter which produce the main and the satellites components of the studied spectral lines.
- Publication:
-
UV Astronomy: Stars from Birth to Death
- Pub Date:
- July 2007
- Bibcode:
- 2007uasb.conf..137L
- Keywords:
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- UV astronomy;
- hot emission stars;
- Si IV;
- DACs;
- SACs