HST OBSERVATIONS OF HOST GALAXIES IN 3 RADIO-SELECTED BL-LACERTAE OBJECTS

We present high-resolution images of three BL Lac objects (0814 + 425, 1823 + 568, 2254 + 074) taken with the WFPC-2 camera on Hubble Space Telescope (HST) as part of a study of BL Lacs from a complete radio-se lected sample. In two cases we clearly detect the host galaxies while the third BL Lac (0814 + 425) is unresolved. The host galaxy of 2254 074 is a moderately bright elliptical, while the inferred luminosity of the host galaxy for 1823 + 568 is at the high end of the range for previously known BL Lac hosts. The lack of detection of a host galaxy for 0814 + 425 calls into question the validity of its low reported re dshift. Comparison of the HST data with subarcsecond ground-based R-ba nd images shows excellent agreement on the largest scales, while on sm aller scales only HST detects the galaxy significantly above the nucle ar light. In the case of 2254 + 074, the high resolution of HST allows us to establish that the host galaxy is an elliptical.