Polarization of Astronomical Maser Radiation. IV. Circular Polarization Profiles
نویسندگان
چکیده
ProÐle comparison of the Stokes parameters V and I is a powerful tool for maser data analysis, which provides the Ðrst direct methods for unambiguous determination of (1) the maser saturation stage, (2) the ampliÐcation optical depth and intrinsic Doppler width of unsaturated masers, and (3) the comparative magnitudes of Zeeman splitting and Doppler line width. Circular polarization recently detected in OH 1720 MHz emission from the Galactic center appears to provide the Ðrst direct evidence for maser saturation. Subject headings : line : proÐles È magnetic Ðelds È masers È polarization È radiative transfer
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