The Zeeman Effect in the Sobolev Approximation II: Split Monopole Fields and the "Heartbeat" Stokes V Profile

K. G. Gayley$^1$, R. Ignace$^2$

$^1$ Department of Physics and Astronomy, University of Iowa
$^2$ Department of Physics and Astronomy, East Tennessee State University

We calculate the circularly polarized Stokes V profile for emission lines, formed in hot-star winds threaded with a weak radial magnetic field. For simplicity, the field is treated as a split monopole under the assumptions that it has been radially combed by the wind, and rotation is not playing a central role. Invoking the weak-field approximation, we find that the V profile has a characteristic ``heartbeat' shape exhibiting multiple sign inversions, which might be mistaken for noise in the absence of theoretical guidance. We also conclude that there is a tendency for the V profile to integrate to zero on each side of the line separately.

Reference: Astrophysical Journal, submitted
Status: Manuscript has been submitted