SCYON Abstract

Received on May 06 2008

The effect of rotation on the abundances of the chemical elements of the A-type stars in the Praesepe cluster

AuthorsL. Fossati (1), S. Bagnulo (2), J. Landstreet (3), G. Wade (4), O. Kochukhov (5), R. Monier (6), W. Weiss (1), and G. Gebran (7)
Affiliation(1) Institut für Astronomie, Universität Wien, Türkenschanzstrasse 17, 1180 Wien, Austria
(2) Armagh Observatory, College Hill, Armagh BT61 9DG, Northern Ireland
(3) Department of Physics & Astronomy, University of Western Ontario, London, N6A 3K7, Ontario, Canada^M
(4) Physics Dept., Royal Military College of Canada, PO Box 17000, Station Forces, K7K 4B4, Kingston, Canada
(5) Department of Astronomy and Space Physics, Uppsala University, 751 20, Uppsala, Sweden ^M
(6)Laboratoire Universitaire d'Astrophysique de Nice, Universite de Nice Sophia-Antipolis, Parc Valrose, 06000 Nice, France
(7) Groupe de Recherches en Astronomie et Astrophysique du Languedoc UMR 5024, Universite' Montpellier II, Place E. Bataillon, 34095 Montpellier, France
Accepted byAstronomy & Astrophysics
Contactfossati@jan.astro.univie.ac.at
URL
Links Praesepe

Abstract

We study how chemical abundances of late B-, A-, and early F-type stars evolve with time, and we search for correlations between the abundance of chemical elements and other stellar parameters, such as effective temperature and υ sin i. We observed a large number of B-, A-, and F-type stars belonging to open clusters of different ages. In this paper we concentrate on the Praesepe cluster (log t = 8.85), for which we have obtained high-resolution, high signal-to-noise ratio spectra of sixteen normal A- and F-type stars and one Am star, using the SOPHIE spectrograph of the Observatoire de Haute-Provence. For all the observed stars, we derived fundamental parameters and chemical abundances. In addition, we discuss another eight Am stars belonging to the same cluster, for which the abundance analysis had been presented in a previous paper. We find a strong correlation between the peculiarity of Am stars and υ sin i. The abundance of the elements underabundant in Am stars increases with υ sin i, while it decreases for the overabundant elements. Chemical abundances of various elements appear correlated with the iron abundance.