1999MNRAS.305...97R

We present intermediate-resolution optical spectropolarimetry of the radio-loud quasar 4C 74.26. Large variations in both the degree and position angle of polarization are observed across the broad H α line. After continuum subtraction, we find that in polarized flux this feature is redshifted by ~ 2000 km.s^–1 relative to its median wavelength in total flux. We show that the H α polarization can be explained by scattering in a high-speed outflow which, if it is directed along the axis of the radio jet, must have a velocity ≥ 5000 km.s^–1 in order to account for the observed redshift. The polarization position angle is not precisely orthogonal to that of the radio source, suggesting that the scattering outflow is either inhomogeneous, or somewhat misaligned with the jet axis.