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arXiv · 1407.8456

Effect of cross-redistribution on the resonance scattering polarization of O {\sc i} line at 1302 \AA\,

L. S. Anusha·K. N. Nagendra·H. Uitenbroek
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Abstract

Oxygen is the most abundant element on the Sun after Hydrogen and Helium. The intensity spectrum of resonance lines of neutral Oxygen namely O {\sc i} (1302, 1305 and 1306 \AA\,) has been studied in the literature for chromospheric diagnostics. In this paper we study the resonance scattering polarization in the O {\sc i} line at 1302 \AA\, using two-dimensional radiative transfer in a composite atmosphere constructed using a two-dimensional magneto-hydrodynamical snapshot in the photosphere and columns of the one-dimensional FALC atmosphere in the chromosphere. The methods developed by us recently in a series of papers to solve multi-dimensional polarized radiative transfer have been incorporated in our new code POLY2D which we use for our analysis. We find that multi-dimensional radiative transfer including XRD effects is important in reproducing the amplitude and shape of scattering polarization signals of the O {\sc i} line at 1302 \AA\,.

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L. S. Anusha, K. N. Nagendra, H. Uitenbroek. 2014-07-31. Effect of cross-redistribution on the resonance scattering polarization of O {\sc i} line at 1302 \AA\,. https://doi.org/10.1088/0004-637x/794/1/17

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