Polarimetry as a tool to study multi-dimensional winds and disks

TL;DR

This paper discusses how polarimetry can be used to investigate the structure and behavior of stellar winds and disks, especially in massive stars, to better understand their mass loss and angular momentum evolution.

Contribution

It highlights the application of linear polarimetry as a diagnostic tool for studying multi-dimensional winds and disks in massive stars, connecting observational techniques with theoretical models.

Findings

Polarimetry distinguishes between polar and equatorial mass loss.

Theories on wind dependence on stellar rotation are tested.

Insights into disk formation mechanisms in B[e] stars.

Abstract

I start with a discussion of spherical winds and small-scale clumping, before continuing with various theories that have been proposed to predict how mass loss depends on stellar rotation -- both in terms of wind strength, as well as the latitudinal dependence of the wind. This very issue is crucial for our general understanding of angular momentum evolution in massive stars, and the B[e] phenomenon in particular. I then discuss the tool of linear polarimetry that allows us to probe the difference between polar and equatorial mass loss, allowing us to test B[e] and related disk formation theories.