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Related papers: Characterizing maser polarization: effects of satu…

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(Abridged) Polarized emission from masers is an excellent tool to study magnetic fields in maser sources. The linear polarization of most masers is understood as an interplay of maser saturation and anisotropic pumping. However, for the…

Astrophysics of Galaxies · Physics 2024-01-10 Boy Lankhaar , Gabriele Surcis , Wouter Vlemmings , Violette Impellizzeri

General solutions of the maser polarization problem are presented for arbitrary absorption coefficients. The results are used to calculate polarization for masers permeated by magnetic fields with arbitrary values of \xB, the ratio of…

Astrophysics · Physics 2009-10-28 Moshe Elitzur

In this paper we investigate the polarization property of the radiation amplified by astronomical masers in the presence of a strong magnetic field. Our model explicitly takes into account the broadband nature of the radiation field and the…

Astrophysics of Galaxies · Physics 2015-05-13 Dinh-V-Trung

We apply the anisotropic resonant scattering model developed to explain the presence of non-Zeeman circular polarization signals recently detected in the $^{12}\mathrm{CO}\;\left(J=2\rightarrow1\right)$ and $\left(J=1\rightarrow0\right)$…

Solar and Stellar Astrophysics · Physics 2015-06-22 Martin Houde

Through polarization observations masers are unique probes of the magnetic field in a variety of different astronomical objects, with the different maser species tracing different physical conditions. In recent years maser polarization…

Astrophysics · Physics 2009-11-13 W. H. T. Vlemmings

Through polarization observations water masers are excellent probes of magnetic fields in the maser region. Magnetic field strengths, such as those in the water masers regions of the envelopes of late-type stars and star-forming regions,…

Astrophysics · Physics 2009-11-11 W. H. T. Vlemmings

The linear polarization that is observed, together with likely changes in the orientation of the magnetic field along the line of sight and hence of the optical axes of the medium, can lead to the circular polarization that is observed in…

Astrophysics · Physics 2009-10-30 D. S. Wiebe , W. D. Watson

SiO masers from AGB stars exhibit variability in intensity and polarization during a pulsation period. This variability is explained by radiative transfer and magnetic properties of the molecule. To investigate this phenomenon, a 3D maser…

Solar and Stellar Astrophysics · Physics 2025-04-23 M. Phetra , M. D. Gray , K. Asanok , S. Etoka , B. H. Kramer , K. Sugiyama , W. Nuntiyakul

We present circular polarization measurements of circumstellar H_2O masers. The circular polarization detected in the (6_{16}-5_{23}) rotational transition of the H_{2}O maser can be attributed to Zeeman splitting in the intermediate…

Astrophysics · Physics 2009-11-07 W. H. T. Vlemmings , P. J. Diamond , H. J. van Langevelde

The detailed polarization mechanisms of SiO masers originating from the near circum\-stellar environment of Asymptotic Giant Branch stars are not yet definitively known. Prevailing theories are broadly classified as either Zeeman or…

Solar and Stellar Astrophysics · Physics 2018-12-27 Taylor L. Tobin , Athol J. Kemball , Malcolm D. Gray

We discuss studies of polarization in astrophysical masers with particular emphasis on the case where the Zeeman splitting is small compared to the Doppler profile, resulting in a blend of the transitions between magnetic substates. A…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Taylor L. Tobin , Malcolm D. Gray , Athol J. Kemball

We present the first circular polarization measurements of circumstellar H2O masers. Previously the magnetic field in circumstellar envelopes has been estimated using polarization observations of SiO and OH masers. SiO masers are probes of…

Astrophysics · Physics 2009-11-06 W. Vlemmings , P. J. Diamond , H. J. van Langevelde

Profile comparison of the Stokes parameters $V$ and $I$ is a powerful tool for maser data analysis, providing the first direct methods for unambiguous determination of (1) the maser saturation stage, (2) the amplification optical depth and…

Astrophysics · Physics 2009-10-30 Moshe Elitzur

The theory of the generation and transfer of polarized radiation, mainly developed for interpreting solar spectropolarimetric observations, allows to reconsider, in a more rigorous and elegant way, a physical mechanism that has been…

Astrophysics · Physics 2009-11-10 A. Asensio Ramos , E. Landi Degl'Innocenti , J. Trujillo Bueno

This paper considers the problem of modeling the light polarization that emerges from an astrophysical plasma composed of atoms whose excitation state is significantly influenced by the anisotropy of the incident radiation field. In…

Solar and Stellar Astrophysics · Physics 2011-05-03 Javier Trujillo Bueno

Calculations are performed for the circular polarization of maser radiation from a turbulent, Keplerian disk that is intended to represent the sub-parsec disk at the nucleus of the galaxy NGC4258. The polarization in the calculations is a…

Astrophysics · Physics 2009-11-06 W. D. Watson , D. S. Wiebe

Context: Ground-state OH maser emission from late-type stars is usually polarized and remains a powerful probe of the magnetic field structure in the outer regions of circumstellar envelopes if observed with high angular and spectral…

Astrophysics of Galaxies · Physics 2011-10-11 Paweł Wolak , Marian Szymczak , Eric Gérard

We study the polarization of the SiO maser emission in a representative sample of evolved stars in order to derive an estimate of the strength of the magnetic field, and thus determine the influence of this magnetic field on evolved stars.…

Astrophysics · Physics 2007-05-23 Fabrice Herpin , Alain Baudry , Clemens Thum , Dave Morris , Helmut Wiesemeyer

We present a stochastic description of multiple scattering of polarized waves in the regime of forward scattering. In this regime, if the source is polarized, polarization survives along a few transport mean free paths, making it possible…

Data Analysis, Statistics and Probability · Physics 2013-07-19 Jérémie Boulanger , Nicolas le Bihan , Vincent Rossetto

We consider astrophysical maser radiation that is created in the presence of mildly supersonic, magnetohydrodynamic (MHD) turbulence. The focus is on the OH masers for which the magnetic field is strong enough that the separations of the…

Astrophysics · Physics 2009-11-10 William D. Watson , Dmitri S. Wiebe , Jonathan C. McKinney , Charles F. Gammie
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