  The eclipsing binary epsilon Aur is unique in being a very long-period binary
involving an evolved, variable F star and a suspected B main-sequence star
enshrouded in an opaque circumstellar disk. The geometrical arrangement is that
the disk is viewed almost perfectly edge-on, with alignment leading to a
partial eclipse of the F star. Despite a global observing campaign for the
2009-11 eclipse, there remain outstanding questions about the nature of the
binary, its components, the disk, and the evolutionary state of the system. We
analyze optical-band polarimetry in conjunction with broad-band color
variations to interpret brightness variations across the surface of the F star.
We model this both during and after the 1982-84 eclipse for which an extensive
and dense data set exists. We develop a model in terms of surface temperature
variations characterized by a small global variation overlaid with a
temperature variation described with low-order spherical harmonics. While not
providing a detailed fit to the dataset, our modeling captures the overall
characterization of the color and polarimetric variability. In particular, we
are able to recover the gross behavior of the polarimetric excursion in the Q-U
plane as observed during eclipse of the F star when compared to post-eclipse
behavior.
