Reference : Calibration of the pre-main sequence RS Chamaleontis binary system
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/75441
Calibration of the pre-main sequence RS Chamaleontis binary system
English
Alecian, E. [Observatoire de Paris, LESIA, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France]
Goupil, Marie-José [Observatoire de Paris, LESIA, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France]
Lebreton, Y. [Observatoire de Paris, GEPI, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France]
Dupret, Marc-Antoine [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique >]
Catala, C. [Observatoire de Paris, LESIA, 5 place Jules Janssen, 92195 Meudon Principal Cedex, France]
1-Apr-2007
Astronomy and Astrophysics
EDP Sciences
465
241-248
Yes (verified by ORBi)
International
0004-6361
1432-0746
Les Ulis
France
[en] stars: pre-main sequence ; stars: binaries: eclipsing ; stars: oscillations stars: evolution ; stars: interiors ; stars: individual: RS chamaleons
[en] Context: The calibration of binary systems with accurately known masses and/or radii provides powerful tools to test stellar structure and evolution theory and to determine the age and helium content of stars. We study the eclipsing double-lined spectroscopic binary system RS Cha, for which we have accurate observations of the parameters of both stars (masses, radii, luminosities, effective temperatures and metallicity). Aims: We have calculated several sets of stellar models for the components of the RS Cha system, with the aim of reproducing simultaneously the available observational constraints and to estimate the age and initial helium abundance of the system. Methods: Using the CESAM stellar evolution code, we model both components starting from the initial mass and metallicity and adjusting the input parameters and physics in order to satisfy the observational constraints. Results: We find that the observations cannot be reproduced if we assume that the abundance ratios are solar but they are satisfied if carbon and nitrogen are depleted in the RS Cha system with respect to the Sun. This is in accordance with the abundances observed in other young stars. The RS Cha system is in an evolutionary stage at the end of the PMS phase where models are not strongly sensitive to various physical uncertainties. However we show that the oscillations of these two stars, which have been detected, would be able to discriminate between different options in the physical description of this evolutionary phase.
http://hdl.handle.net/2268/75441
10.1051/0004-6361:20065822
http://adsabs.harvard.edu/abs/2007A%26A...465..241A
http://de.arxiv.org/abs/astro-ph/0610947

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Open access
aa5822-06.pdfNo commentaryPublisher postprint343.93 kBView/Open

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.