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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.
(Abridged.) We present F435W (B), F606W (Broad V), and F814W (Broad I) coronagraphic images of the debris disk around Beta Pictoris obtained with HSTs Advanced Camera for Surveys. We confirm that the previously reported warp in the inner disk is a di
We use HST/ACS observations of the spiral galaxy M51 in F435W, F555W and F814W to select a large sample of star clusters with accurate effective radius measurements in an area covering the complete disc of M51. We present the dataset and study the ra
We present the structural parameters of 99 Super Star Clusters (SSCs) in the Disk of M82. Moffat-EFF, King and Wilson models were fitted using a chi^2 minimisation method to background-subtracted Surface Brightness Profiles (SBPs) in F435W (B), F555W
Hubble Space Telescope Advanced Camera for Surveys images of the young binary GG Tauri and its circumbinary disk in V and I bandpasses were obtained in 2002 and are the most detailed of this system to date. The confirm features previously seen in the
This is the first paper of a series describing our measurement of weak lensing by large-scale structure using archival observations from the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). In this work we present result