Theory weekly seminar (TWS)
A magnetic massive star has experienced a stellar merger
A magnetic massive star has experienced a stellar merger
Dr. Amin Farhang - School of Astronomy
19 MAY 2024
15:00 - 16:00
Abstract:
Massive stars (those ≥8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7% of massive stars have observed magnetic fields, the origin of which is debated. We used multi- epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than its companion. The system properties and a surrounding bipolar nebula can be reproduced with a model in which two stars merged (in a previous triple system) to produce the magnetic massive star. Our results provide observational evidence that magnetic fields form in at least some massive stars through stellar mergers.
Meeting Place:
Seminar Room, School of Particles and Accelerators, IPM
Link to Join Virtually:
https://meet.google.com/fnv-dfkk-ghb
Link: https://meet.google.com/fnv-dfkk-ghb