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Quantum interference effects play a vital role in shaping the linear polarization profiles of solar spectral lines. The Ba II D2 line at 4554 A is a prominent example, where the F-state interference effects due to the odd isotopes produce…

Solar and Stellar Astrophysics · Physics 2015-06-15 H. N. Smitha , K. N. Nagendra , J. O. Stenflo , M. Sampoorna

The long-standing paradox of the linear polarization signal of the Na i D1 line was recently resolved by accounting for the atom's hyperfine structure and the detailed spectral structure of the incident radiation field. That modeling relied…

Solar and Stellar Astrophysics · Physics 2023-09-25 Gioele Janett , Ernest Alsina Ballester , Luca Belluzzi , Tanausú del Pino Alemán , Javier Trujillo Bueno

Angle-frequency coupling in scattering of polarized light on atoms is represented by the angle-dependent (AD) partial frequency redistribution (PRD) matrices. There are several lines in the linearly polarized solar spectrum, for which PRD…

Solar and Stellar Astrophysics · Physics 2020-07-29 K. N. Nagendra , K. Sowmya , M. Sampoorna , J. O. Stenflo , L. S. Anusha

The Sc II 4247 A line formed in the chromosphere is one of the lines well known, like the Na I D_2 and Ba II D_2, for its prominent triple peak structure in Q/I and the underlying quantum interference effects governing it. In this paper, we…

Solar and Stellar Astrophysics · Physics 2015-06-22 H. N. Smitha , K. N. Nagendra , J. O. Stenflo , M. Bianda , R. Ramelli

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

Partial frequency redistribution (PRD), describing the formation of the line profile, has negligible observational effects for optical depths smaller than ~10^3, at the resolving power of most current instruments. However, when the spectral…

Earth and Planetary Astrophysics · Physics 2015-05-27 Roxana E. Lupu , Paul D. Feldman , Stephan R. McCandliss , Darrell F. Strobel

Quantum interference phenomena manifests itself in several ways in the polarized solar spectrum formed due to coherent scattering processes. One such effect arises due to interference between the fine structure (J) states giving rise to…

Solar and Stellar Astrophysics · Physics 2015-06-11 H. N. Smitha , K. Sowmya , K. N. Nagendra , M. Sampoorna , J. O. Stenflo

Context. The correct modeling of the scattering polarization signals observed in several strong resonance lines requires taking partial frequency redistribution (PRD) phenomena into account. Aims. This work aims at assessing the impact and…

Recent theoretical investigations have pointed out that the cores of the Ly-alpha lines of H I and He II should show measurable scattering polarization signals when observing the solar disk, and that the magnetic sensitivity, through the…

Solar and Stellar Astrophysics · Physics 2015-06-05 Luca Belluzzi , Javier Trujillo Bueno , Jiri Stepan

$F$-state interference significantly modifies the polarization produced by scattering processes in the solar atmosphere. Its signature in the emergent Stokes spectrum in the absence of magnetic fields is depolarization in the line core. In…

Solar and Stellar Astrophysics · Physics 2015-12-25 K. Sowmya , K. N. Nagendra , J. O. Stenflo , M. Sampoorna

The scattering polarization in the solar spectrum is traditionally modeled with each spectral line treated separately, but this is generally inadequate for multiplets where J-state interference plays a significant role. Through simultaneous…

Solar and Stellar Astrophysics · Physics 2015-06-04 H. N. Smitha , K. N. Nagendra , J. O. Stenflo , M. Bianda , M. Sampoorna , R. Ramelli , L. S. Anusha

Although the h and k lines of MgII are expected to be of great interest for probing the upper solar chromosphere, relatively little is known about their polarization properties which encode the information on the magnetic field. Here we…

Solar and Stellar Astrophysics · Physics 2015-06-04 Luca Belluzzi , Javier Trujillo Bueno

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

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…

The linear polarization signals produced by scattering processes in strong resonance lines are rich in information on the magnetic and thermal structure of the chromosphere and transition region of the Sun and of other stars. A correct…

Solar and Stellar Astrophysics · Physics 2015-06-19 Luca Belluzzi , Javier Trujillo Bueno

The quantum interference between the fine structure states of an atom modifies the shapes of the emergent Stokes profiles in the Second Solar Spectrum. This phenomenon has been studied in great detail both in the presence and absence of…

Solar and Stellar Astrophysics · Physics 2015-06-22 K. Sowmya , K. N. Nagendra , M. Sampoorna , J. O. Stenflo

The solution of polarized radiative transfer equation with angle-dependent (AD) partial frequency redistribution (PRD) is a challenging problem. Modeling the observed, linearly polarized strong resonance lines in the solar spectrum often…

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

Radiative transfer modeling of spectral lines including partial redistribution (PRD) effects requires the evaluation of the ratio of the emission to the absorption profile. This quantity requires a large amount of computational work if one…

Solar and Stellar Astrophysics · Physics 2015-06-05 Jorrit Leenaarts , Tiago Pereira , Han Uitenbroek

Approximated forms of the RII and RIII redistribution matrices are frequently applied to simplify the numerical solution of the radiative transfer problem for polarized radiation, taking partial frequency redistribution (PRD) effects into…

Solar and Stellar Astrophysics · Physics 2023-11-29 Simone Riva , Nuno Guerreiro , Gioele Janett , Diego Rossinelli , Pietro Benedusi , Rolf Krause , Luca Belluzzi

Aims: Main goal of this work is to study the potential of He II Ly-alpha wavelength-integrated scattering polarisation for probing the magnetism of the solar upper chromosphere. Methods: Radiative transfer calculations are performed in…

Solar and Stellar Astrophysics · Physics 2024-08-14 F. Riva , G. Janett , L. Belluzzi
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