相关论文: Maser polarization through anisotropic pumping

The polarization of masers contains information on the magnetic field strength and direction of the regions they occur in. Many maser polarization observations have been performed over the last 30 years. However, versatile maser…

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…

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…

We present a survey of the polarization properties of mm-wavelength methanol masers, comprising both classes, and transitions from 84.5 to 157.0 GHz. Linear polarization is found in more than half of the observed objects, and circular…

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…

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…

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 $\left(J=1\rightarrow0\right)$…

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…

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…

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…

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…

Context. The high intensities and narrow bandwidths exhibited by some astronomical masers make them ideal tools for studying star-forming giant molecular clouds. The water maser transition $J_{K_{-1}K_{1}}=5_{32}-4_{41}$ at 620.701 GHz can…

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…

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…

A sufficient condition for maser instability in a weakly magnetized relativistic plasma with an isotropic particle distribution function is given. The maser growth rates and polarizations are computed starting from the exact dielectric…

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…

We observed polarization of the SiO rotational transitions from Orion Source I (SrcI) to probe the magnetic field in bipolar outflows from this high mass protostar. Both 43 GHz $J$=1-0 and 86 GHz $J$=2-1 lines were mapped with $\sim$20 AU…

We have used the Very Large Array (VLA) at 7 mm wavelength to image five rotational transitions (J=1-0) from three SiO isotopologues towards Orion BN/KL: 28SiO v=0,1,2; and 29SiO and 30SiO v=0. For the first time, we have mapped the 29SiO…

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…

(Abridged) Astronomical masers have been effective tools to study magnetic fields for many years. In particular, methanol can be used to probe different parts of protostars such as accretion discs and outflows, since it produces one of the…