Bibcode
Martin, E. L.; Magazzu, A.
Referencia bibliográfica
ASP Conf. Ser. 154, The Tenth Cambridge Workshop on Cool Stars, Stellar Systems and the Sun, Edited by R. A. Donahue and J. A. Bookbinder, p.1742
Fecha de publicación:
0
1998
Número de citas
2
Número de citas referidas
2
Descripción
We present mid-resolution spectroscopic observations of 35 stars
reported to be weak T Tauri stars (WTTS) discovered by ROSAT in the
Taurus-Auriga star-forming region (Wichmann et al. 1996). We have
measured the equivalent widths of Hα and Li 1 670.8 nm in our
spectra. On the basis of our higher-resolution data, we reassess the
evolutionary status of these stars. Most of the stars in the Wichmann
sample coming from ROSAT pointed observations are confirmed to be WTTSs.
However, only a minority (18%) of the stars discovered in the ROSAT
all-sky survey (RASS) really are WTTSs. It appears that the RASS sources
are mainly older stars (PTTSs, ZAMS and dMe). Our results do not support
previous suggestions about the existence of a numerous population of
WTTSs widely dispersed around molecular clouds.