Searching for Magnetic Fields in the Descendants of Massive OB Stars

TL;DR

This study surveys late-type supergiants, descendants of massive OB stars, using spectropolarimetry to detect magnetic fields, revealing complex Zeeman signatures in a significant fraction of the sample.

Contribution

It provides the first systematic detection of magnetic fields in cool supergiants, expanding understanding of magnetic phenomena in evolved massive stars.

Findings

Detectable magnetic fields in a significant fraction of supergiants

Complex Zeeman signatures observed in Stokes V profiles

First systematic survey of magnetism in this stellar class

Abstract

We present the results of a recent survey of cool, late-type supergiants - the descendants of massive O- and B-type stars - that has systematically detected magnetic fields in these stars using spectropolarimetric observations obtained with ESPaDOnS at the Canada-France-Hawaii Telescope. Our observations reveal detectable, often complex, Stokes V Zeeman signatures in Least-Squares Deconvolved mean line profiles in a significant fraction of the observed sample of ~30 stars.