Near-IR spectropolarimetry and modeling of NGC 1068

Abstract

We present new spectropolarimetric data for NGC 1068, including, for the first time, coverage in the near-IR. Using these, and other previously published data, we develop a scattering model for NGC 1068, using NGC 5548 for the underlying Seyfert 1 continuum spectrum and M31 for the stellar contribution. Although electron scattering is the dominant process, if NGC 5548 is typical of Seyfert 1s in the near-IR then electron scattering alone cannot be soley responsible for the observed polarization of NGC 1068 at these wavelengths, and a contribution from dichroic absorption of the radiation from the IR-emitting regions of the active nucleus, through the postulated torus, is required. The extinction in this region is A_V>=45 mag, although we note that the extinction to broad-line region and nucleus is much higher.