EDP Sciences
Free access
Volume 392, Number 3, September IV 2002
Page(s) 869 - 884
Section Stellar clusters and associations
DOI http://dx.doi.org/10.1051/0004-6361:20020984

A&A 392, 869-884 (2002)
DOI: 10.1051/0004-6361:20020984

Characteristics of new star cluster candidates in the Cygnus area

J.-M. Le Duigou and J. Knödlseder

Centre d'Étude Spatiale des Rayonnements, CNRS/UPS, BP 4346, 31028 Toulouse Cedex 4, France
    e-mail: Jean-Michel.LeDuigou@cnes.fr; knodlseder@cesr.fr
(Received 12 April 2002 / Accepted 6 June 2002 )

The morphology and stellar content of 22 clusters in the Cygnus area has been determined using 2MASS infrared observations in the  J and K bands. 7 of the clusters are well-known objects and our results are in good agreement with previous work. 12 objects are recently-discovered cluster candidates (Dutra & Bica 2001) and 3 are new cluster candidates. Adopting distance estimates from the literature or by considering cluster counterparts, we derive a consistent set of parameters suitable for analysis and comparison: center coordinates, radius, stellar population, IMF slope and mass range. We find a mean IMF slope of $\Gamma=-1.30$ for the known clusters and $\Gamma=-1.40$ for the others. Infrared data having better completeness, we derive larger stellar contents and cluster masses than previous works. An important fraction of the cluster stellar population in Cygnus is hidden in very obscured areas. A clear tendency towards mass segregation appears for most of the clusters. Some of the new clusters seem to be quite massive, probably hosting very massive stars at the center. They are privileged targets for more detailed investigations using infrared spectroscopy.

Key words: stars: early-type -- ISM:dust: extinction -- open clusters and associations: individual: Cygnus -- Galaxy: stellar content

Offprint request: J.-M. Le Duigou, Jean-Michel.LeDuigou@cnes.fr

SIMBAD Objects in preparation

© ESO 2002