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Related papers: Scattering polarization in solar flares

200 papers

We study the broadband polarization of hydrogen lines produced by scattering of radiation, in the presence of isotropic electric fields. In this paper, we focus on two distinct problems: a) the possibility of detecting the presence of…

Astrophysics · Physics 2024-09-04 R. Casini , R. Manso Sainz

Polarisation measurements of solar flares at millimetre-waves were used to investigate the magnetic field configuration of the emitting sources. We analyse two solar flares (SOL2013-02-17 and SOL2013-11-05) observed by the POlarisation…

Solar and Stellar Astrophysics · Physics 2020-05-05 Douglas F. da Silva , Paulo J. A. Simões , R. F. Hidalgo Ramírez , Adriana Válio

The linear polarization produced by scattering processes in the hydrogen Lyman alpha line of the solar disk radiation is a key observable for probing the chromosphere-corona transition region (TR) and the underlying chromospheric plasma.…

Solar and Stellar Astrophysics · Physics 2019-08-14 Ernest Alsina Ballester , Luca Belluzzi , Javier Trujillo Bueno

We derive exact expressions for the degree of lineal polarization over a resolved or integrated stellar disc due to resonance scattering and the Hanle effect from a dipolar or quadrupolar distribution of magnetic fields. We apply the theory…

Solar and Stellar Astrophysics · Physics 2015-06-11 R. Manso Sainz , M. J. Martínez González

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

The surfaces of neutron stars are likely sources of strongly polarized soft X rays due to the presence of strong magnetic fields. Scattering transport in the surface layers is critical to the determination of the emergent anisotropy of…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Kun Hu , Matthew G. Baring , Joseph A. Barchas , George Younes

The intense magnetic fields of neutron stars naturally lead to strong anisotropy and polarization of radiation emanating from their surfaces, both being sensitive to the hot spot position on the surface. Accordingly, pulse phase-resolved…

High Energy Astrophysical Phenomena · Physics 2025-02-21 Matthew G. Baring , Hoa Dinh Thi , George A. Younes , Kun Hu

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

The weak, turbulent magnetic fields that supposedly permeate most of the solar photosphere are difficult to observe, because the Zeeman effect is virtually blind to them. The Hanle effect, acting on the scattering polarization in suitable…

Solar and Stellar Astrophysics · Physics 2015-05-19 F. Snik , A. G. de Wijn , K. Ichimoto , C. E. Fischer , C. U. Keller , B. W. Lites

We present multilevel radiative transfer modeling of the scattering polarization observed in the solar O I infrared triplet around 777 nm. We demonstrate that the scattering polarization pattern observed on the solar disk forms in the…

Solar and Stellar Astrophysics · Physics 2015-08-06 T. del Pino Alemán , J. Trujillo Bueno

Radiative transfer (RT) studies of the linearly polarized spectrum of the Sun (the second solar spectrum) have generally focused on the line formation, with an aim to understand the vertical structure of the solar atmosphere using…

Solar and Stellar Astrophysics · Physics 2013-08-16 L. S. Anusha , K. N. Nagendra

Velocity gradients in a stellar atmospheric plasma have an impact on the anisotropy of the radiation field that illuminates each point within the medium, and this may in principle influence the scattering line polarization that results from…

Solar and Stellar Astrophysics · Physics 2015-06-11 E. S. Carlin , A. Asensio Ramos , J. Trujillo Bueno

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

Recent spectropolarimetric observations of Herbig AeBe stellar systems show linear polarization variability with wavelength and epoch near their obscured H-alpha emission. Surprisingly, this polarization is not coincident with the H-alpha…

Astrophysics · Physics 2009-11-13 J. R. Kuhn , S. V. Berdyugina , D. M. Fluri , D. M. Harrington , J. O. Stenflo

We investigate the main physical mechanisms that shape the intensity and polarization of the Ba II D1 line at 4934 angstroms via radiative transfer numerical experiments. We focus especially on the scattering linear polarization arising…

Solar and Stellar Astrophysics · Physics 2024-01-24 E. Alsina Ballester , T. del Pino Alemán , J. Trujillo Bueno

We describe how the observed polarization properties of an astronomical object are related to its intrinsic polarization properties and the finite temporal and spectral resolutions of the observing device. Moreover, we discuss the effect…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Paz Beniamini , Pawan Kumar , Ramesh Narayan

In this work the polarizability of a subwavelength core-shell sphere is considered, where the shell exhibits a radially inhomogeneous permittivity profile. A mathematical treatment of the elec- trostatic polarizability is formulated in…

Optics · Physics 2018-11-14 Dimitrios C. Tzarouchis , Ari Sihvola

The polarization of radiation by scattering on an atom embedded in combined external quadrupole electric and uniform magnetic fields is studied theoretically. Limiting cases of scattering under Zeeman effect and Hanle effect in weak…

Astrophysics · Physics 2015-06-24 Yee Yee Oo , M. Sampoorna , K. N. Nagendra , Sharath Ananthamurthy , G. Ramachandran

Optical spectropolarimetry and broadband polarimetry in other wavebands has been a key to understanding many diverse aspects of AGN. In some cases polarization is due to synchrotron radiation, and in other cases it's due to scattering.…

Astrophysics · Physics 2007-05-23 R. R. J. Antonucci

We report polarization tomography experiments on metallic nanohole arrays with square and hexagonal symmetry. As a main result, we find that a fully polarized input beam is partly depolarized after transmission through a nanohole array.…