A Unification of X-ray selected BL Lacs and FRI Radio Galaxies

In this work, we revisit the unification scheme using the radio observations of X-ray selected BL Lacertae objects (XBLs) and FRI radio galaxies. The results are: 1) BL Lacertae objects and FRI radio galaxies show similar extended radio luminosity, and 2) In the luminosity and core-dominance plot, BL Lacertae objects and FRI radio galaxies are located in the same region, suggesting a unification of XBLs and FRI radio galaxies.