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Hidden bipolarity in red supergiant winds

A. M. S. Richards·M. R. W. Masheder·H. J. van Langevelde·R. J. Cohen·M. D. Gray·J. A. Yates·P. J. Diamond·W. H. T. Vlemmings·M. Szymczak·K. Murakawa
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Abstract

Many observations of late-type M stars show large near-spherical circumstellar envelopes, yet planetary nebulae and supernova remnants are frequently axisymmetric. We present VLBI and MERLIN observations of masers around the red supergiant S Per which show varying degrees of axisymmetry and a dynamically significant magnetic field. There is no evidence for rotation here or in most similar objects. We examine possible origins of the magnetic field.

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A. M. S. Richards, M. R. W. Masheder, H. J. van Langevelde, R. J. Cohen, M. D. Gray, J. A. Yates, P. J. Diamond, W. H. T. Vlemmings, M. Szymczak, K. Murakawa. 2005-01-03. Hidden bipolarity in red supergiant winds. https://arxiv.org/abs/astro-ph/0501028

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