EDP Sciences
Free access
Volume 418, Number 1, April IV 2004
Page(s) 89 - 98
Section Galactic structure, stellar clusters and populations
DOI http://dx.doi.org/10.1051/0004-6361:20034510

A&A 418, 89-98 (2004)
DOI: 10.1051/0004-6361:20034510

The IC 2118 association: New T Tauri stars in high-latitude molecular clouds

M. Kun1, T. Prusti2, S. Nikolic3, 4, L. E. B. Johansson4 and N. A. Walton5

1  Konkoly Observatory, 1525 Budapest, PO Box 67, Hungary
2  Astrophysics Missions Division, Research and Scientific Support Department of ESA, Postbus 299, 2200 AG Noordwijk, The Netherlands
3  Astronomical Observatory, Volgina 7, 11160 Belgrade 74, Serbia, Serbia and Montenegro
4  Onsala Space Observatory, 439 92 Onsala, Sweden
5  Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK

(Received 14 October 2003 / Accepted 21 January 2004)

We identified new pre-main sequence stars in the region of high-latitude molecular clouds associated with the reflection nebula IC 2118, around $l \sim 208\degr$ and $b \sim -27\degr$. The stars were selected as T Tauri candidates in objective prism plates obtained with the Schmidt telescope of Konkoly Observatory. Results of spectroscopic follow-up observations, carried out with the FLAIR spectrograph installed on the UK Schmidt and with ALFOSC on Nordic Optical Telescope, are presented in this paper. Based on spectral types, presence of emission lines and lithium absorption line, we identified five classical T Tauri stars and a candidate weak-line T Tauri star projected on the molecular clouds, as well as two candidate pre-main sequence stars outside the nebulous region. Using the near infrared magnitudes obtained from the 2MASS All Sky Catalog (IPAC 2003) we determined the masses and ages of these stars. We found that the five classical T Tauri stars projected on the clouds are physically related to them, whereas the other stars are probably background objects. Adopting a distance of 210 pc for IC 2118 (Kun et al. 2001) and using Palla & Stahler's (1999) evolutionary tracks we derived an average age of $2.5\times10^{6}$ yrs and a mass interval of 0.4-1.0 $M_\odot$ for the members of the IC 2118 association.

Key words: ISM: clouds -- ISM: individual objects: IC 2118 -- stars: formation -- stars: pre-main sequence

Offprint request: M. Kun, kun@konkoly.hu

SIMBAD Objects

© ESO 2004