Magnetism of hot stars

TL;DR

This paper reviews the properties, recent discoveries, and theoretical understanding of magnetic fields in hot O- and B-type stars, highlighting their influence on stellar winds, mass loss, and evolution.

Contribution

It provides a comprehensive overview of the characteristics of magnetic hot stars, recent advances, and theoretical progress in understanding their magnetic fields and evolutionary impact.

Findings

Magnetic fields are present in a small fraction of hot stars.

Magnetic fields influence stellar winds and rotation.

Recent theoretical models improve understanding of magnetic field origins and effects.

Abstract

Strong, stable, and organised magnetic fields are present at the surfaces of a small fraction of OBA stars. These "fossil fields" exhibit uniform characteristics in stars over a tremendous range of stellar mass, age, temperature, and rotation rate. In hot O- and B-type stars, these magnetic fields couple efficiently to the stellar radiatively driven winds, strongly influencing stellar mass loss and rotation. In this article we review the characteristics of the known magnetic hot stars, discuss recent discoveries and insights, and describe recent theoretical progress toward understanding basic field properties and the influence of magnetic fields on hot star evolution.