VLA studies of X-ray selected BL Lacertae objects

Observations of 13 X‐ray selected BL Lacertae objects (X‐BL Lacs) from the HEAO‐1 Large Area Sky Survey have been obtained with the Very Large Array. These X‐BL Lacs are Fanaroff‐Riley I radio sources, and are less core‐dominated than traditional radio selected BL Lacs (R‐BL Lacs). The radio properties are consistent with a ‘‘unified scheme’’ connecting BL Lacs with FR I radio galaxies, where X‐BL Lacs are oriented at larger angles to the line‐of‐sight than R‐BL Lacs. However, the X‐ray emission does not appear to be as strongly relativistically beamed as the radio and may be completely unbeamed.