Rapid Variations in the Broad Hβ Profile of the Radio Galaxy 3C 390.3: Possible Evidence for Turbulence in the Accretion Disk

We report on implications for the geometrical and kinematic parameters of BLR gas on the basis of short timescale variability in the broad Hβ profile. Data on rapid variations have been obtained at the 6-m telescope of the SAO (Asatrian, Khachikian & Notni, 1999). To search for variations in the profile shape, difference spectra (first minus second epoch) were examined. We believe that the structure of the underlying stellar continuum and the atmospheric features do not affect the Hβ difference profiles of 3C 390.3 significantly. Variations occurred simultaneously on the blue and red sides of Hβ on a timescale of ~ 1.452 hours and take the form of three narrow, positive and negative small bumps drifting across the line profile in the difference spectrum. The positions of the bumps are −2300, +4700 (negative) and −3700 kms 2212;1 (positive).