A SIGNATURE OF RELATIVISTIC ELECTRON-POSITRON BEAMS IN BL LACERTAE OBJECTS

BL Lacertae objects have been observed to vary in all wavebands on var ious timescales ranging from years to hours. Compton Gamma Ray Observa tory (CGRO) observations have revealed intense gamma-ray emission from several BL Lac Objects. We show here that there is a significant corr elation between the Doppler-corrected minimal X-ray luminosity and the equivalent timescale of X-ray variability extrapolated from the obser ved optical variability for BL Lac objects. We interpret this as evide nce for relativistic electron-positron beams in BL Lac objects.