Low mass B stars with low surface gravity.
Abstract
Summary. A series of static models of stars with inert, isothermal helium cores (X =0.0; Z =0.03) and thin hydrogen-burning shells has been calculated. The mass range covered is 0.26A).5 M0. All core masses are more than 98 % of the total stellar mass. The envelope composition is X =0.7, Z =0.03. The models have log Teff from 4.0 to 5.0; log L/L0 from 1.4 to 3.6; log g from 1.8 to 5.9; and evolutionary time scales of t0 to 4 x 106 years, the last massive evolving most slowly. The sequences of models are a good approximation to evolutionary tracks in the region they cover. A 0.3 to 0.4 M0 model will pass through a stage which closely resembles the primary component of HZ 22 in mass, temperature, luminosity, and surface gravity with a time scale of about t0 years. Key words: HZ 22 - static models - B stars
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 1973
- Bibcode:
- 1973A&A....23..281T