The ACS Virgo Cluster Survey. VI. Isophotal Analysis and the Structure of Early‐Type Galaxies

(Abridged) We present a detailed analysis of the morphology, isophotalparameters and surface brightness profiles for 100 early-type members of theVirgo Cluster, from dwarfs (M_B = -15.1 mag) to giants (M_B = -21.8 mag). Eachgalaxy has been imaged in two filters, closely resembling the Sloan g and zpassbands, using the Advanced Camera for Surveys on board the Hubble SpaceTelescope. Dust and complex morphological structures are common, with kiloparsec-scalestellar disks, bars, and nuclear stellar disks seen in 60% of galaxies withintermediate luminosity (-20 < M_B < -17), and dust seen in 42% of galaxiesbrighter than M_B = -18.9 mag. Dust morphologies range from faint wisps andpatches on tens of parsec scales, to regular, highly organized kpc-scale dustdisks, often showing evidence of recent star formation. Surface brightness profiles and isophotal parameters are derived typicallywithin 8 kpc from the center for the brightest galaxies, and 1.5 kpc for thefaintest systems, with a resolution (FWHM) of 7 pc. Based on a parametrizationof the surface brightness profiles in terms of a Sersic or core-Sersic model,we find that 1) there is no evidence of a bimodal behavior of the slope, gamma,of the profile in the innermost regions; 2) although the brightest galaxieshave shallow inner profiles, the shallowest profiles (lowest gamma values) arefound in faint dwarf systems; 3) the widely adopted separation of early-typegalaxies between "core" and "power-law" types, which had originally beenprompted by the claim of a clear bimodal distribution of gamma values, isuntenable; and 4) there is no evidence of a structural dichothomy between dwarfand regular ellipticals.