Ultraviolet Spectropolarimetry With Polstar: Using Polstar to test Magnetospheric Mass-loss Quenching

TL;DR

Polstar, a proposed NASA space telescope, aims to use ultraviolet spectropolarimetry to investigate how magnetospheres influence mass-loss and angular momentum in hot stars, enhancing understanding of stellar evolution.

Contribution

This paper proposes using Polstar's ultraviolet spectropolarimetry to test the impact of magnetospheres on mass-loss and star spin-down in hot stars, a novel observational approach.

Findings

Magnetospheres may significantly reduce stellar mass-loss rates.

Magnetospheres could lead to rapid stellar spin-down.

Differences in evolution between magnetic and non-magnetic stars are expected.

Abstract

Polstar is a proposed NASA MIDEX space telescope that will provide high-resolution, simultaneous full-Stokes spectropolarimetry in the far ultraviolet, together with low-resolution linear polarimetry in the near ultraviolet. This observatory offers unprecedented capabilities to obtain unique information on the magnetic and plasma properties of the magnetospheres of hot stars. We describe an observing program making use of the known population of magnetic hot stars to test the fundamental hypothesis that magnetospheres should act to rapidly drain angular momentum, thereby spinning the star down, whilst simultaneously reducing the net mass-loss rate. Both effects are expected to lead to dramatic differences in the evolution of magnetic vs. non-magnetic stars.