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Polarization and Extent of Maser Emission from Late-Type Stars: Support for a Plasma Turbulence Model of Maser Production

Stacy Palen
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Abstract

The integrated spectrum of OH emission from late-type stars is often circularly polarized, by as much as 50% in some cases. While the spectra are partially polarized, the individual maser components revealed by VLBI are much more so. Using VLBI observations of late-type stars from the literature, we show that the difference in circular polarization between main lines correlates with a difference in angular extent for a given object. This is a natural result if turbulent magnetic fields are causing the masers to be polarized via the Cook mechanism, and might serve as a good diagnostic for determining which objects should be investigated in the search for magnetic fields around evolved stars.

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Stacy Palen. 2000-10-17. Polarization and Extent of Maser Emission from Late-Type Stars: Support for a Plasma Turbulence Model of Maser Production. https://doi.org/10.1086/318874

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