Semiregular variables of types SRa and SRb - Basic properties in the visual and the IRAS-range
- Author(s)
- Franz Kerschbaum, Josef Hron
- Abstract
The pulsational properties, T(eff)s, mass loss rates, luminosities, scale heights, and volume densities in the Galactic plane are presented for samples of optical semiregular variables of types SRa and SRb correlated with the IRAS point source catalog. These properties are compared to the corresponding characteristics of optical Mira variables. It is found that the SRa's are not a distinct class of variables but a mixture of 'intrinsic' Miras and SRb's. The O-rich SRb's form a quite homogeneous group in terms of periods, amplitudes, and temperatures. They consist of a 'blue' group with no indication of circumstellar shells, with P less than 150 d and T(eff) greater than 3200 K, and a 'red' group with temperatures and mass loss rates comparable to Miras but periods about a factor of two smaller. The C-rich SRVs generally have smaller periods and are more abundant than C-rich Miras. The evolutionary status of the SRVs is discussed.
- Organisation(s)
- Department of Astrophysics
- Journal
- Astronomy & Astrophysics
- Volume
- 263
- Pages
- 97 - 112
- No. of pages
- 16
- ISSN
- 0004-6361
- Publication date
- 09-1992
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy, 103004 Astrophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/semiregular-variables-of-types-sra-and-srb--basic-properties-in-the-visual-and-the-irasrange(1594da36-3589-4b91-8d93-60cfc0cc881c).html