Evolutionary effects in atmospheres of red horizontal branch stars
Abstract
Abundance anomalies caused by the mixing to the surface of material processed in nuclear reactions inside a star are dependent on parameters of stellar atmospheres (e.g. the effective temperature, gravity and overall metallicity). However, a variety of evolved stars investigated is rather limited. In our study, we present results for 20 cool, metal-abundant stars with a double energy source (helium burning in the centre and hydrogen burning in the shell). High resolution spectroscopic observations of these stars were accomplished on the Nordic Optical Telescope. The main atmospheric parameters and abundances of more than twenty chemical elements, including 12C, 13C, N, O, Na, Mg and Al, were determined and evolutionary effects investigated.
- Publication:
-
IAU Joint Discussion
- Pub Date:
- 2000
- Bibcode:
- 2000IAUJD...5E..33T