A&A 465, 593-601 (2007)
DOI: 10.1051/0004-6361:20066633
A critical test of empirical mass loss formulas applied to individual giants and supergiants
K.-P. Schröder1, 2 and M. Cuntz3, 41 Departamento de Astronomía, A. P. 144, Universidad de Guanajuato, 36000 Guanajuato, GTO, Mexico
e-mail: kps@astro.ugto.mx
2 Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany
3 Department of Physics, Science Hall, University of Texas at Arlington, Arlington, TX 76019-0059, USA
e-mail: cuntz@uta.edu
4 Institut für Theoretische Astrophysik, Universität Heidelberg, Albert Überle Str. 2, 69120 Heidelberg, Germany
(Received 24 October 2006 / Accepted 10 January 2007)
Abstract
To test our new, improved Reimers-type mass-loss relation, given by
Schröder & Cuntz in 2005 (ApJ, 630, L73), we take a look at the best studied
galactic giants and supergiants - particularly those with spatially resolved circumstellar shells and winds, obtained directly or by means of a companion acting as a probing light source.
Together with well-known physical parameters, the selected stars provide the
most powerful and critical observational venues for assessing the validity of
parameterized mass-loss relations for cool winds not driven by molecules or
dust. In this study, star by star, we compare our previously published
relation with the original Reimers relation (1975, Mem. Roy. Soc. Liège 6. Ser. 8, 369), the Lamers relation
(1981, ApJ, 245, 593), and the two relations by de Jager and his group (1988, A&AS, 72, 259; 1990, A&A, 231, 134).
The input data,
especially the stellar masses, have been constrained using detailed stellar
evolution models. We find that only the relationship by Schröder & Cuntz
agrees, within the error bars, with the observed mass-loss rates for all giants
and supergiants.
Key words: methods: statistical -- stars: general -- stars: late-type -- stars: mass-loss -- stars: winds, outflows
© ESO 2007

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