| This thesis presents synthetic spectra and response functions of the red giant stellar line emission model of active galactic nuclei (e.g., Kazanas 1989). Our results agree with the fundamental line emission characteristics of active galactic nuclei within the model uncertainties if the following new assumptions are made: (1) the mean stellar mass loss rates decrease with distance from the black hole, and (2) the mean ionization parameters are lower than those postulated in Kazanas (1989). Models with enhanced mass loss predict minimum line/continuum delays that are proportional to the zero-intensity-full-width of the profiles. Because of the high column densities we assumed, these models also predict triangle-shaped response functions, which are not generally observed. Models without enhanced mass loss yield line-continuum delays that are proportional to the square root of the continuum luminosity. This prediction appears to agree with results from reverberation mapping campaigns.; If the intercloud (interstellar) medium densities are high enough, the winds are “comet-shaped,” with the shock fronts having higher densities than the cloud “tails.” In this case, the densities in the ionized inverse Strömgren regions of the outbound clouds are lower than those of the inbound clouds. For models in which an accretion disk occults the broad line region, the broadest line emission and absorption profile components of lines similar to C IV, N V, and O VI are redshifted. Conversely, the narrowest emission and absorption profile components are blueshifted. The shifts of the Lyman alpha profile components are relatively small. One particularly interesting prediction of the nonspherical wind models is that their C IV red wings respond faster than their blue wings, as has been observed (e.g., Done & Krolik 1996). These same models, however, yield opposite results for the C III] line, such that the C III] blue wings respond first. Measurements of the velocity dependence of the C III] profile response, therefore, could be used to test the viability of nonspherical stellar wind line emission models. |
