1996A&A...310..533H

We present high-S/N spectropolarimetry of the Hα emission line of ζ Puppis. We discuss, and successfully remove, a high-frequency instrumental signature. The corrected data show polarization structure through the emission line, which we attribute to an equatorial density enhancement of the wind. We employ simple (core-halo) numerical models to derive a lower limit of a factor of 1.3 to the implied equator-to-pole density ratio, and to demonstrate that the wind structure predicted by wind-compression theory is capable of reproducing the gross characteristics of the polarization spectrum.