Lanthanides and other spectral oddities in a Centauri
Abstract
Context: There is considerable interest in the helium variable a Cen as a bridge between helium-weak and helium-strong CP stars. Aims: We investigate Ce III and other possible lanthanides in the spectrum the of hottest chemically peculiar (CP) star in which these elements have been found. A {Kr II line appears within a broad absorption which we suggest may be due to a high-level transition in C II. Methods: Wavelengths and equivalent widths are measured on high-resolution UVES spectra, analyzed, and their phase-variations investigated. Results: New, robust identifications of Ce III and Kr II are demonstrated. Nd III is likely present. A broad absorption near 4619[A] is present at all phases of a Cen, and in some other early B stars. Conclusions: The presence of lanthanides in a Cen strengthens the view that this star is a significant link between the cooler CP stars and the hotter helium-peculiar stars. Broad absorptions in a Cen are not well explained.
Keywords
Cite
@article{arxiv.1010.3355,
title = {Lanthanides and other spectral oddities in a Centauri},
author = {C. R. Cowley and S. Hubrig and J. F. Gonzalez},
journal= {arXiv preprint arXiv:1010.3355},
year = {2017}
}
Comments
Research Note accepted by Astronomy and Astrophysics; 4 pages, 4 Figs. 2 Tables