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arXiv · 0912.3467

Recovering the Line-Of-Sight Magnetic Field in the Chromosphere from Ca II IR Spectra

F. Wöger·S. Wedemeyer-Böhm·H. Uitenbroek·T. Rimmele
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Abstract

We propose a method to derive the line-of-sight magnetic flux density from measurements in the chromospheric Ca II IR line at 854.2 nm. The method combines two well-understood techniques, the center-of-gravity and bisector methods, in a single hybrid technique. The technique is tested with magneto-static simulations of a flux tube. We apply the method to observations with the Interferometric Bidimensional Spectrometer (IBIS) installed at the Dunn Solar Telescope of the NSO/SP to investigate the morphology of the lower chromosphere, with focus on the chromospheric counterparts to the underlying photospheric magnetic flux elements.

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F. Wöger, S. Wedemeyer-Böhm, H. Uitenbroek, T. Rimmele. 2009-12-17. Recovering the Line-Of-Sight Magnetic Field in the Chromosphere from Ca II IR Spectra. https://arxiv.org/abs/0912.3467

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