出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：A physical understanding of the dynamics in the broad line region is essential for an explanation of the narrowness of the permitted lines in Narrow-Line Seyfert 1 galaxies. We have looked at the stability of orbits in the presence of radiation pressure. We find that for strong radiative support, circular orbits are unstable, and an inward perturbation pushes the cloud on an eccentric orbit which produces a narrow line profile. We have also looked at the hydrodynamic stability of clouds using axisymmetric simulations. A purely azimuthal magnetic field leads to quick cloud destruction via Mathew’s pancake mechanism. An additional poloidal component may inhibit this particular mechanism.
