A detailed abundance analysis of five field blue horizontal-branch (or BHB) stars, namely Feige 86, HD 128801, HD 143459, HD 213781 and HZ 27 is presented. Spectra obtained at ESO with UVES found in the archives for Feige 86 and recent ESPaDOnS spectra from CFHT obtained by the authors for the four other stars of the sample are analysed. Since atomic diffusion can occur in the atmospheres of hot BHB stars, this study aims to verify if vertical abundance stratification is present in these stars. The abundance of each selected atomic line is obtained by line fitting using the ZEEMAN2 code. Since the various atomic lines of a given species are formed at different depths in the atmosphere, a search for potential vertical abundance stratification is therefore possible. Average abundances are also estimated, along with the rotational and radial velocities of each star. When possible, these values are compared to previous studies.
American Astronomical Society Meeting Abstracts #227
- Pub Date:
- January 2016