On the absolute scale of mass-loss in red giants. I. Circumstellar absorption lines in the spectrum of the visual companion of alpha 1Her.
Abstract
Summary. Mass-loss from oci Her (MS II) is rediscussed on the basis of new measurements and observations of circumstellar absorption lines in the spectrum of its visual companion 2 Her. The rate of mass-loss is 2.710-8 M0/yr. Masses, luminosities and evolutionary stages of the components of cc Her are discussed. For cci Her, we find Mv = -0.3+04 M= 1.7 M0 and a position very near to the tip of the 1. giant branch or on the 2. giant branch. L Assuming a mass4oss relation M[M0/yr] = [solar units], a calibration through cc1 Her yields c=1. which is lower by a factor of 3 than originally suggested (Reimers, 1975). It is pointed out that whatever the method of determination-the absolute scale of mass-losses from red giants is uncertain by factors of at least two either way due to our poor knowledge of luminosities and metal abundances of M giants. Key words: mass-loss red giant stars stellar evolution
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1977
- Bibcode:
- 1977A&A....61..217R
- Keywords:
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- Absorption Spectra;
- Companion Stars;
- Red Giant Stars;
- Stellar Mass Ejection;
- Stellar Spectra;
- Abundance;
- M Stars;
- Stellar Evolution;
- Stellar Luminosity;
- Stellar Mass;
- Astrophysics