Abstract
We study the stellar cluster population in M81, using the HST/ACS images in the filters F435W, F606W and F814W that cover a total field of view of ∼140 arcmin^2. We present details about the selection criteria, which were based both on morphological and photometrical features. The extracted sample of stellar clusters shows the presence of two cluster populations, a blue cluster group (young) with 560 objects, and a red cluster group (old) with 120 objects. The young group lacks clusters more massive than 104 M_⊙, that are present in large numbers in its neighbor M82. The luminosity distribution function of the young group follows a power-law distribution with α = 2.0, whereas that for the red group resembles very much the globular cluster luminosity function in the Milky Way. Assuming an age of 5 Gyr, these red clusters have masses between 105 and 107 M_⊙.
