¹ Smithsonian Astrophysical Observatory, 60 Garden St. MS 15 Cambridge, MA 02138 USA
² Dept of Optics and Quantum Electronics, Univ. of Szeged, Dom tér 9. Szeged, Hungary H-6720

We analyze spectra of 44 emission line stars detected in a low resolution optical spectroscopic survey of the galactic open cluster NGC 6871. The survey of 1217 stars is complete to V=14.9 and includes stars with V<16.5 between the zero age main sequence (ZAMS) and the 10⁷ yr pre-main sequence (PMS) isochrone. Of the 44 emission line stars in this survey, 28 show obvious emission in H and 16 have weak H absorption (compared to H). We use the reddening to separate foreground and background stars from the cluster members; the position in the HR diagram (HRD) or the presence of forbidden emission lines ([NII], [SII]) then yields the evolutionary status of the emission line stars. A comparison of the H spectral index distribution in NGC 6871 with the distribution of young stars in the Taurus-Auriga molecular cloud indicates that the late type PMS stars in our sample may be weak line T Tauri stars (wTTs). Many of these stars show [SII] (36%) and [NII] (45%) emission.

Accepted by AJ
Preprints from zbalog@cfa.harvard.edu