Investigation of the Monoceros Star-Forming Complex Using uvbyβ Photometry

An overall uvbyβ photometric investigation of the Monoceros star-forming complex has been undertaken. We study a large field covering 14x14 deg in Galactic coordinates and present a homogeneous database of the most current uvbyβ photometry for stars of all stellar types and luminosity classes. The photometry is used to establish a homogeneous distance scale for the stellar groupings as well as the field stars. The clusters and field stars have been mapped and their spatial structures have been studied. The layers of field stars are used to investigate the distribution of interstellar matter toward Mon OB1 association and an increase in the interstellar absorption has been noticed at 500 pc. The color magnitude diagrams and the spatial stellar distribution for the most prominent clusters in the field NGC 2244 and NGC 2264 imply possible sub-structures.