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تسجيل مستخدم جديدSurface magnetism of cool giant and supergiant stars
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Heidi Korhonen
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The existence of starspots on late-type giant stars in close binary systems, that exhibit rapid rotation due to tidal locking, has been known for more than five decades. Photometric monitoring spanning decades has allowed studying the long-term magnetic activity in these stars revealing complicated activity cycles. The development of observing and analysis techniques that has occurred during the past two decades has also enabled us to study the detailed starspot and magnetic field configurations on these active giants. In the recent years magnetic fields have also been detected on slowly rotating giants and supergiant stars. In this paper I review what is known of the surface magnetism in the cool giant and supergiant stars.
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The recent years have brought great advances in our knowledge of magnetic fields in cool giant and supergiant stars. For example, starspots have been directly imaged on the surface of an active giant star using optical interferometry, and magnetic fi
elds have been detected in numerous slowly rotating giants and even on supergiants. Here, I review what is currently known of the magnetism in cool giant and supergiant stars, and discuss the origin of these fields and what is theoretically known about them.
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