Red noise and pulsations in evolved massive stars

Abstract

We examine high-cadence space photometry taken by the Transiting Exoplanet Survey Satellite (TESS) of a sample of evolved massive stars (26 Wolf-Rayet stars and 8 Luminous Blue Variables or candidate LBVs). To avoid confusion problems, only stars without bright Gaia neighbours and without evidence of bound companions are considered. This leads to a clean sample, whose variability properties should truly reflect the properties of the WR and LBV classes. Red noise is detected in all cases and its fitting reveals characteristics very similar to those found for OB-stars. Coherent variability is also detected for 20% of the WR sample. Most detections occur at moderately high frequency (3--14/d), hence are most probably linked to pulsational activity. This work doubles the number of WRs known to exhibit high-frequency signals.

accepted by MNRAS - the arxiv version has some figures in low-resolution

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Cited by in corpus (6)

• An all-sky sample of intermediate- to high-mass OBA-type eclipsing binaries observed by TESS
• The IACOB project VIII. Searching for empirical signatures of binarity in fast-rotating O-type stars
• Extreme mass ratios and fast rotation in three massive binaries
• Diving into the magnetosphere of the Of?p star HD108
• The magnetic, spectroscopic, and photometric variability of the Wolf-Rayet star WR55
• Revisiting the orbital motion of WR 138