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arXiv · 0704.3135

Opposite magnetic polarity of two photospheric lines in single spectrum of the quiet Sun

R. Rezaei·R. Schlichenmaier·W. Schmidt·O. Steiner
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Abstract

We study the structure of the photospheric magnetic field of the quiet Sun by investigating weak spectro-polarimetric signals. We took a sequence of Stokes spectra of the Fe I 630.15 nm and 630.25 nm lines in a region of quiet Sun near the disk center, using the POLIS spectro-polarimeter at the German VTT on Tenerife. The line cores of these two lines form at different heights in the atmosphere. The 3$σ$ noise level of the data is about 1.8 $\times 10^{-3} I_{c}$. We present co-temporal and co-spatial Stokes-$V$ profiles of the Fe I 630 nm line pair, where the two lines show opposite polarities in a single spectrum. We compute synthetic line profiles and reproduce these spectra with a two-component model atmosphere: a non-magnetic component and a magnetic component. The magnetic component consists of two magnetic layers with opposite polarity: the upper one moves upwards while the lower one moves downward. In-between, there is a region of enhanced temperature. The Stokes-$V$ line pair of opposite polarity in a single spectrum can be understood as a magnetic reconnection event in the solar photosphere. We demonstrate that such a scenario is realistic, but the solution may not be unique.

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R. Rezaei, R. Schlichenmaier, W. Schmidt, O. Steiner. 2007-05-09. Opposite magnetic polarity of two photospheric lines in single spectrum of the quiet Sun. https://doi.org/10.1051/0004-6361%3A20077441

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