J/A+A/278/36 J/A+A/278/36 M 31 new OB associations E A Magnier P Battinelli W H G Lewin Z Haiman J Van Paradijs G Hasinger W Pietsch R Supper J Truemper Astron. Astrophys. 278 36 1993 1993A&A...278...36M II/208 : BVRI CCD photometry in the field of M 31 (Magnier+ 1992) Associations, stellar Positional data galaxies: individual (M 31) galaxies: spiral galaxies: star clusters methods: data analysis A new identification of OB associations in M 31 has been performed using the Path Linkage Criterion technique of Battinelli (1991A&A...244...69B). We found 174 associations with a very small contamination (<5%) by random clumps stars. The expected total number and average size of OB associations in the region of M 31 covered by our data set (Magnier et al., 1992, Cat. <II/208>) are ~280 and ~90pc, respectively. M 31 associations therefore have sizes similar to those of OB associations observed in nearby galaxies, so that we can consider them to be classical OB associations. This list of OB associations will be used for the study of the spatial distribution of OB associations and their correlation with other objects. Taking into account the fact that we do not cover the entire disk of M 31, we extrapolate a total number of associations in M 31 of ~420.

MLB93 OB association number --- RAdeg Right ascension (J2000.0) deg DEdeg Declination (J2000.0) deg Diam Clump diameter pc NStar Number of stars --- James Marcout, Patricia Bauer CDS 1997Sep26 UNKNOWN UNKNOWN Prepared via OCR at CDS. J_A+A_278_36.xml