Searching for Weak or Complex Magnetic Fields in Polarized Spectra of Rigel

TL;DR

This study analyzed high-resolution spectropolarimetric data of Rigel to search for weak or complex magnetic fields, providing constraints on its magnetic properties and examining spectral line variability.

Contribution

It presents the first detailed spectropolarimetric analysis of Rigel aimed at detecting or constraining weak magnetic fields in a supergiant star.

Findings

No definitive magnetic field detected in Rigel.

Constraints placed on the strength and complexity of possible magnetic fields.

Analysis of spectral line variability related to stellar activity.

Abstract

Seventy-eight high-resolution Stokes V, Q and U spectra of the B8Iae supergiant Rigel were obtained with the ESPaDOnS spectropolarimeter at CFHT and its clone NARVAL at TBL in the context of the Magnetism in Massive Stars (MiMeS) Large Program, in order to scrutinize this core-collapse supernova progenitor for evidence of weak and/or complex magnetic fields. In this paper we describe the reduction and analysis of the data, the constraints obtained on any photospheric magnetic field, and the variability of photospheric and wind lines.