Polarization of Quasars: Rotated and Funnel-shaped Outflow
  Polarization is a useful probe to investigate the geometries and dynamics of outflow in BAL QSOs. We perform a Monte-Carlo simulation to calculate the polarization produced by resonant and electron scattering in BALR. We find: 1)A rotated and funnel-shaped outflow is preferred to explain many observed polarization features. 2)The resonant scattering can contribute a significant part of NV emission line in some QSOs. 
Hui-Yuan Wang, Ting-Gui Wang and Jun-Xian Wang