|
Description
We present results of an extensive search for weak-line T Tauri stars (WTTS) in the outskirts of the Taurus-Auriga molecular cloud on the basis of the ROSAT All-Sky Survey Bright Source Catalog (Cat. <IX/10>). Our surveyed region extends from 2h 40m to 5h 40m in right ascension and from 10deg to 40deg in declination, with the central part of Taurus-Auriga(4h<{alpha}<5h, 15deg<{delta}<34deg), accomplished by Wichmann et al. (1996, Cat. <J/A+A/312/439>), excluded. Within a sky coverage of about 10$^{3}$ square degrees, 219 X-ray sources fullfill the criteria for selecting program sources suggested by Neuhauser et al. (1995A&A...295L...5N) and 164 of these X-ray sources were found to have at least one optical counterpart with E magnitude brighter than 16. Low-resolution spectroscopic observation has been carried out in order to discard early type stars and galaxies from the sample, additional intermediate-resolution spectra of a sub-sample of 156 late type optical counterparts were obtained for spectral classification and for the calculation of the equivalent width of H{alpha} emission and LiI line absorption at 6707{AA}. Excluding 2 previously identified WTTS, a total of 75 new candidate WTTS and one possible classical T Tauri star have been discovered in our study. The majority of the newly found Li-rich optical counterparts are believed to b e PMS stars rather than ZAMS stars as those of the Pleiades.
|
