Issue |
A&A
Volume 473, Number 3, October III 2007
|
|
---|---|---|
Page(s) | L21 - L24 | |
Section | Letters | |
DOI | https://doi.org/10.1051/0004-6361:20078276 | |
Published online | 28 August 2007 |
Letter to the Editor
The evolution of stars in the Taurus-Auriga T association*
1
Institut d'Astrophysique, 98bis Bd. Arago, 75014 Paris, France e-mail: claude.bertout@obspm.fr
2
Institut d'Astronomie et d'Astrophysique, Université Libre de Bruxelles, CP 226, 1050 Brussels, Belgium
3
LERMA, Observatoire de Paris, 61 Av. de l'Observatoire, 75014 Paris, France
Received:
13
July
2007
Accepted:
20
August
2007
In a recent study, individual parallaxes were determined for
many stars of the Taurus-Auriga T association that are members
of the same moving group.
We use these new parallaxes to re-address the issue of the relationship
between classical T Tauri stars (CTTSs) and weak-emission line
T Tauri stars (WTTSs). With the available spectroscopic and photometric information for 72
individual stars or stellar systems among the Taurus-Auriga objects
with known parallaxes, we derived reliable photospheric
luminosities, mainly from the Ic magnitude of these objects. We
then studied the mass and age distributions of the stellar sample,
using pre-main sequence evolutionary models to determine the basic
properties of the stellar sample. Statistical tests and Monte Carlo
simulations were then applied to studying the properties of the two
T Tauri subclasses. We find that the probability of CTTS and WTTS samples being drawn from the same
parental age and mass distributions is low; CTTSs are, on average,
younger than WTTSs. They are also less massive, but this is due to
selection effects. The observed mass and age
distributions of both T Tauri subclasses can be understood in the framework of a
simple disk evolution model, assuming that the CTTSs evolve into
WTTSs when their disks are fully accreted by the stars. According to
this empirical model, the average disk lifetime in Taurus-Auriga is
yr.
Key words: stars: formation / stars: pre-main sequence / stars: circumstellar matter
© ESO, 2007
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.