A search for peculiar objects in young open clusters I. New emission line and late spectral type stars in NGC 6871

We present the first results of a search in young open clusters for stars o f very high initial mass, carried out by means of slitless spectroscopy. A deep (R similar or equal to 17) survey of the open cluster NGC 6871 reveals many new objects of late spectral type, including an S star, as well as th ree new emission line stars, which are classified as Be stars. The already known Be star HD 227733 is surrounded by a previously undetected reflection nebula. The star VES 145, classified as an emission line object: is actual ly a late-type star, without any emission feature. We argue that VES 145 is a young RSG of a very high. mass (M-0 similar or equal to 25 M-circle dot) and a cluster member.