Bibcode
Alsina Ballester, E.; Belluzzi, L.; Trujillo Bueno, J.
Bibliographical reference
The Astrophysical Journal, Volume 836, Issue 1, article id. 6, 15 pp. (2017).
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2
2017
Journal
Citations
27
Refereed citations
25
Description
The spectral line polarization encodes a wealth of information about the
thermal and magnetic properties of the solar atmosphere. Modeling the
Stokes profiles of strong resonance lines is, however, a complex problem
both from a theoretical and computational point of view, especially when
partial frequency redistribution (PRD) effects need to be taken into
account. In this work, we consider a two-level atom in the presence of
magnetic fields of arbitrary intensity (Hanle–Zeeman regime) and
orientation, both deterministic and micro-structured. Working within the
framework of a rigorous PRD theoretical approach, we have developed a
numerical code that solves the full non-LTE radiative transfer problem
for polarized radiation, in one-dimensional models of the solar
atmosphere, accounting for the combined action of the Hanle and Zeeman
effects, as well as for PRD phenomena. After briefly discussing the
relevant equations, we describe the iterative method of solution of the
problem and the numerical tools that we have developed and implemented.
We finally present some illustrative applications to two resonance lines
that form at different heights in the solar atmosphere, and provide a
detailed physical interpretation of the calculated Stokes profiles. We
find that magneto-optical effects have a strong impact on the linear
polarization signals that PRD effects produce in the wings of strong
resonance lines. We also show that the weak-field approximation has to
be used with caution when PRD effects are considered.
Related projects
Magnetism, Polarization and Radiative Transfer in Astrophysics
Magnetic fields pervade all astrophysical plasmas and govern most of the variability in the Universe at intermediate time scales. They are present in stars across the whole Hertzsprung-Russell diagram, in galaxies, and even perhaps in the intergalactic medium. Polarized light provides the most reliable source of information at our disposal for the
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