Please use this identifier to cite or link to this item:
Title: Barium stars, galactic populations and evolution
Author: Mennessier, M. O.
Luri Carrascoso, Xavier
Figueras Siñol, Francesca
Gómez, A.E.
Grenier, S.
Torra Roca, Jorge
North, P.
Keywords: Estels
Cinemàtica galàctica
Estadística matemàtica
Galactic kinematics
Mathematical statistics
Issue Date: 30-Apr-1997
Publisher: EDP Sciences
Abstract: In this paper HIPPARCOS astrometric and kinematical data together with radial velocities from other sources are used to calibrate both luminosity and kinematics parameters of Ba stars and to classify them. We confirm the results of our previous paper (where we used data from the HIPPARCOS Input Catalogue), and show that Ba stars are an inhomogeneous group. Five distinct classes have been found i.e. some halo stars and four groups belonging to disk population: roughly super-giants, two groups of giants (one on the giant branch, the other at the clump location) and dwarfs, with a few subgiants mixed with them. The confirmed or suspected duplicity, the variability and the range of known orbital periods found in each group give coherent results supporting the scenario for Ba stars that are not too highly massive binary stars in any evolutionary stages but that all were previously enriched with Ba from a more evolved companion. The presence in the sample of a certain number of ``false'' Ba stars is confirmed. The estimates of age and mass are compatible with models for stars with a strong Ba anomaly. The mild Ba stars with an estimated mass higher than 3Msun_ may be either stars Ba enriched by themselves or ``true'' Ba stars, which imposes new constraints on models.
Note: Reproducció del document publicat a:
It is part of: Astronomy & Astrophysics, 1997, vol. 326, num. 2, p. 722-730
ISSN: 0004-6361
Appears in Collections:Articles publicats en revistes (Física Quàntica i Astrofísica)

Files in This Item:
File Description SizeFormat 
121510.pdf216.53 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.