HST Observations of X-ray-selected AGN

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We report on the initial results of a comprehensive Hubble Space Telescope (HST) snapshot imaging survey of 76 low redshift (z < 0.15) X-ray-selected active galactic nuclei (AGN) in the Einstein Extended Medium Sensitivity Survey. This survey is expected to show no bias with respect to host galaxy types and so is arguably one of the best available samples with HST imaging for the study of the host galaxies. The HST observations in the F814W band are complemented by deeper ground-based observations in the B and R bands for all AGN. The absolute magnitudes for AGN in this sample lie in the range -24 < MB(AB) < -18, bracketing the extrapolated break in the QSO luminosity function (MB(AB)= -22.3) at these low redshifts. We find a weak correlation between the luminosity of the host galaxy and the central AGN. We find no convincing cases of an AGN with no detectable host galaxy, although the faintest host galaxies of moderately luminous AGN do extend as faint as MB(AB) = - 18. We find no evidence for strong interaction/merger activity in any of the AGN in this sample. (abstract truncated)