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Magnetic Fields in the envelopes of late-type stars: Circular Polarization of H2O Masers

W. H. T. Vlemmings·P. J. Diamond·H. J. van Langevelde
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Abstract

We present the first circular polarization measurements of circumstellar water masers around a sample of late-type stars. These observations are used to obtain the magnetic field strength in the water maser region with both an LTE and non-LTE analysis. We find fields from a few hundred milliGauss up to a few Gauss, indicating a solar-type r^(-2) dependence of the magnetic field on the distance. No linear polarization is detected to less than 1%.

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W. H. T. Vlemmings, P. J. Diamond, H. J. van Langevelde. 2002-08-02. Magnetic Fields in the envelopes of late-type stars: Circular Polarization of H2O Masers. https://doi.org/10.1007/978-94-010-0139-7_67

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