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arXiv · 1607.05683

Magnetic Diagnostics of the Solar Chromosphere with the Mg II h-k Lines

Tanausú del Pino Alemán·Roberto Casini·Rafael Manso Sainz
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Abstract

We investigated the formation of the Mg II h-k doublet in a weakly magnetized atmosphere (20-100 G) using a newly developed numerical code for polarized RT in a plane-parallel geometry, which implements a recent formulation of partially coherent scattering by polarized multi-term atoms in arbitrary magnetic field regimes. Our results confirm the importance of partial redistribution effects in the formation of the Mg II h and k lines, as pointed out by previous work in the non-magnetic case. We show that the presence of a magnetic field can produce measurable modifications of the broadband linear polarization even for relatively small field strengths (~10 G), while the circular polarization remains well represented by the classical magnetograph formula. Both these results open an important new window for the weak-field diagnostics of the upper solar atmosphere.

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Tanausú del Pino Alemán, Roberto Casini, Rafael Manso Sainz. 2016-07-19. Magnetic Diagnostics of the Solar Chromosphere with the Mg II h-k Lines. https://doi.org/10.3847/2041-8205/830/2/l24

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