No CrossRef data available.
Published online by Cambridge University Press: 12 April 2016
Many years of monitoring a sample of 10 AGNs with a median sampling rate of about one spectrum per week yields strong evidence that broad-line profile variations are not induced by reverberation effects, but rather signify real changes in the structure of the continuum-source and broad-line region complex, contrary to line flux variations, which do respond to continuum variations. If the profile variations indeed trace internal changes in the BLR, then the BLR cannot consist of the billions of small clouds as the standard model of the BLR prescribes. Rather, small-number statistics are necessary. The sample of AGNs also indicates there are three preferred ‘components’ in the line profiles. These can be explained as geometrical projection effects due to an anisotropic continuum irradiating an otherwise spherical BLR.