Compact star clusters in the M31 disk

The UBVRI photometry of 285 cluster candidates (V<~20.5mag) was performed using frames of the Local Group Galaxies Survey. The final sample, containing 238 high probability star cluster candidates (typical half-light radius r_h_~1.5pc), was selected by specifying a lower limit of r_h_>~0.15" (>~0.6pc).

We derived cluster parameters based on the photometric data and multiband images by employing simple stellar population models. The clusters have a wide range of ages from ~5Myr (young objects associated with 24um and/or H{alpha} emission) to ~10Gyr (globular cluster candidates), and possess mass in a range of 3.0<~log(m/m_{sun}_)<~4.3 peaking at m~4000m_{sun}_. Typical age of these intermediate-mass clusters is in the range of 30Myr<~t<~3Gyr, with a prominent peak at ~70Myr.