MAGNETIC FIELDS IN THE ENVELOPES OF LATE-TYPE STARS Circular Polarization of H2O Masers
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چکیده
We present the first circular polarization measurements of circumstellar H2O masers around a sample of late-type stars. These observations are used to obtain the magnetic field strength in the H2O 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 dependence of the magnetic field on the distance. No linear polarization is detected to less than 1%.
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تاریخ انتشار 2002