Hubble space telescope snapshot survey of 3CR quasars: The data

We present images taken with the Wide Field Planetary Camera (WFPC-2) on th e Hubble Space Telescope (HST) of 43 quasars selected from the 3CR radio ca talog. The redshift range of the targets is large-0.3 less than or similar to z less than or similar to 2-and allows us to probe the nature of quasar hosts from about 20% to 80% of the age of the universe. These data were tak en in the course of a large program that imaged 267 3CR radio galaxies and quasars using the HST in "snapshot" mode. Each quasar was centered on the P lanetary Camera (PC1) and was imaged through the F702W filter (bandpass sim ilar to Cousins R). Typical integration times were 5 and 10 minutes. For ea ch quasar, we attempted to judge the contribution of the host galaxy to the total light from the quasar in two ways. The first method was to compare t he radial light distributions of the quasars with that of both model point spread function and an empirical PSF constructed by summing individual obse rvations of standard stars. Second, to provide morphological information we attempted to remove the contribution of the quasar nucleus from the extend ed emission by subtracting a point spread function constructed from observa tions of standard stars. This second method proved to be more sensitive in detecting marginally extended emission. Our analysis suggests that the quasar fuzz contributes from less than 5% to nearly 100% in the most extreme case (about 20% being typical) of the tota l light from the quasar, with 16 of the quasars (similar to 40%) being unre solved according to the analysis of their light profiles (with only 7 being considered unresolved determined by PSF subtraction of the quasar images). The magnitudes of the hosts range from about 18 to more than 21 in the F70 2W filter and the sizes are typically 1 "-2 " at a limiting surface brightn ess of similar to 21-22m(F702W) arcsec(-2). Comparisons with the few ground -based images that are available of these sources suggest good overall morp hological agreement with the HST images. The 0 ".1 resolution of the HST PC combination reveals a wide variety of structures in the host galaxies of t hese quasars. Most of the host galaxies show twisted, asymmetric, or distor ted isophotes. About 1/4 of the quasar hosts have close (within a few arcse conds) companions seen in projection and about 1/10 show obvious signs of t idal interactions with a close companion. Finally, using radio images avail able from the literature, we find that in many of the resolved sources ther e is a correspondence between the radio and optical morphologies. We find t hat these sources exhibit a tendency for the principal axes of the radio an d optical emission to align similar but perhaps weaker than that observed f or radio galaxies. This correspondence also suggests that our methodology f or removing the point source contribution from the resolved emission is sou nd. A more complete analysis of these data and new HST snapshot data will b e presented in subsequent papers.