  We present the results obtained from an objective search for stellar
clusters, both in the currently active nuclear starburst region, and in the
post-starburst disk of M82. Images obtained with the HST/ACS in F435W(B),
F555W(V), and F814W(I) filters were used in the search for the clusters. We
detected 653 clusters of which 393 are located outside the central 450 pc in
the post-starburst disk of M82. The luminosity function of the detected
clusters show an apparent turnover at B=22 mag (M_B=-5.8), which we interpret
from Monte Carlo simulations as due to incompleteness in the detection of faint
clusters, rather than an intrinsic log-normal distribution. We derived a
photometric mass of every detected cluster from models of simple stellar
populations assuming a mean age of either an 8 (nuclear clusters) or 100 (disk
clusters) million years old. The mass functions of the disk (older) and the
nuclear (younger) clusters follow power-laws, the former being marginally
flatter (alpha=1.5+/-0.1) than the latter (alpha=1.8+/-0.1). The distribution
of sizes (Full Width at Half Maximum) of clusters brighter than the apparent
turn-over magnitude (mass>2E+4 Mo) can be described by a log-normal function.
This function peaks at 10 pc for clusters more massive than 1E+5 Mo, whereas
for lower masses, the peak is marginally shifted to larger values for the
younger, and smaller values for the older clusters. The observed trend towards
flattening of the mass function with age, together with an over-abundance of
older compact clusters, imply that cluster disruption in M82 is both dependent
on the mass and size of the clusters.
