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Related papers: Polarized Line Formation in Multi-Dimensional Medi…

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We study the effects of Rayleigh and Raman scattering on the formation of polarized spectral lines in a $\Lambda$-type multi-term atom. We fully take into account the partial redistribution of frequency and the presence of atomic…

Solar and Stellar Astrophysics · Physics 2016-06-29 R. Casini , R. Manso Sainz

To interpret observations of astrophysical disks it is essential to understand the formation process of the emitted light. If the disk is optically thick, scattering dominated and permeated by a Keplerian velocity field, Non-Local…

Solar and Stellar Astrophysics · Physics 2014-11-19 Ivan Milic , Marianne Faurobert

In this work we present a method for generating random matrices describing electromagnetic scattering from disordered media containing dielectric particles with prescribed single particle scattering characteristics. Resulting scattering…

Optics · Physics 2022-12-15 Niall Byrnes , Matthew R. Foreman

This paper presents a detailed study of the scattering polarization profiles formed under partial frequency redistribution (PRD) in two thermal models of the solar atmosphere. Particular attention is given to understanding the influence of…

Solar and Stellar Astrophysics · Physics 2010-10-12 M. Sampoorna , J. Trujillo Bueno , E. Landi Degl'Innocenti

One of the greatest challenges in solar and stellar physics in coming years will be to observe the Second Solar Spectrum with a spatial resolution significantly better than 1 arcsec. This type of scattering polarization observations would…

Astrophysics · Physics 2009-11-13 Javier Trujillo Bueno , Nataliya Shchukina

This article presents an introduction to optical pumping, atomic polarization and the Hanle effect in weakly magnetized stellar atmospheres. Although the physical processes and the theoretical framework described here are of interest for…

Astrophysics · Physics 2007-05-23 Javier Trujillo-Bueno

In the present paper we consider the problem of resonance line polarization formed in the spherically symmetric expanding atmospheres. For the solution of the concerned polarized transfer equation we use the comoving frame formulation, and…

Solar and Stellar Astrophysics · Physics 2020-01-20 A. Megha , M. Sampoorna , K. N. Nagendra , L. S. Anusha , K. Sankarasubramanian

Solar magnetic fields alter scattering polarization in spectral lines like Sr I at 4607 {\AA} via the Hanle effect, making it a potential diagnostic for small-scale mixed-polarity photospheric magnetic fields. Recently, observational…

Solar and Stellar Astrophysics · Physics 2024-02-08 Franziska Zeuner , Tanausú del Pino Alemán , Javier Trujillo Bueno , Sami K. Solanki

Diagnostic techniques for stellar magnetic fields based upon spectropolarimetry. We propose and explore a new technique based upon the linear polarization emitted in Hanle-sensitive lines in disk-integrated stars where a dipolar magnetic…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. López Ariste , A. Asensio Ramos , C. González Fernández

The main goal of this thesis has been to investigate the effects that the macroscopic vertical velocity fields have on the scattering polarization signals formed in the solar chromosphere. Until now, the impact of macroscopic motions had…

Solar and Stellar Astrophysics · Physics 2014-02-10 Edgar S. Carlin Ramírez

Line scattering polarization can be strongly affected by Rayleigh scattering by neutral hydrogen and Thompson scattering by free electrons. Often a continuum depolarization results, but the Doppler redistribution produced by the continuum…

Solar and Stellar Astrophysics · Physics 2015-06-18 T. del Pino Alemán , R. Manso Sainz , J. Trujillo Bueno

Several strong solar resonance lines show observable linear scattering polarization signals, holding a great potential for investigating the magnetism of the outer solar atmosphere. Accurately modeling these signals requires solving the…

Principal contributions to QED radiative effects for Moller scattering of polarized particles are investigated both on the Born level and taking into account radiative corrections (RC). Scattering on the case of longitudinal and transversal…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. M. Shumeiko , J. G. Suarez

Using a quantum electrodynamical approach, we derive the scattering phase matrices for polarized radiation involving forbidden line transitions and in the presence of an external magnetic field. The case of (J=0->2->0) scattering is…

Astrophysics · Physics 2008-05-27 Yee Yee Oo , Phyu Phyu San , M. Sampoorna , K. N. Nagendra , G. Ramachandran

Highly precise numerical solutions to the radiative transfer equation with polarization present a special challenge. Here, we establish a precise numerical solution to the radiative transfer equation with combined Rayleigh and isotropic…

Classical Physics · Physics 2018-03-14 B. D. Ganapol

Resonance spectral lines such as H I Ly {\alpha}, Mg II h&k, and Ca II H&K that form in the solar chromosphere are influenced by the effects of 3D radiative transfer as well as partial redistribution (PRD). So far no one has modeled these…

Solar and Stellar Astrophysics · Physics 2016-12-28 Andrii V. Sukhorukov , Jorrit Leenaarts

A general theoretical framework is developed for interpreting spectropolarimetric observations of optically thin emission line scattering from small dust particles. Spatially integrated and spatially resolved line profiles of both scattered…

Astrophysics · Physics 2009-10-22 W. J. Henney

The Hanle effect in strong spectral lines is the physical mechanism that should be increasingly exploited for quantitative explorations of the magnetism of the quiet solar chromospheric plasma. Here we show, by means of multilevel radiative…

Solar and Stellar Astrophysics · Physics 2011-02-25 Jiri Stepan , Javier Trujillo Bueno , Renzo Ramelli , Michele Bianda

Linearly polarized emission is described, in general, in terms of the Stokes parameters $Q$ and $U$, from which the polarization intensity and polarization angle can be determined. Although the polarization intensity and polarization angle…

Astrophysics of Galaxies · Physics 2018-01-31 C. A. Herron , B. M. Gaensler , G. F. Lewis , N. M. McClure-Griffiths

The polarization of radiation by scattering on an atom embedded in combined external quadrupole electric and uniform magnetic fields is studied theoretically. Analytic formulae are derived for the scattering phase matrix. Limiting cases of…

Astrophysics · Physics 2007-05-23 Yee Yee Oo , K. N. Nagendra , Sharath Ananthamurthy , G. Ramachandran