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arXiv · 1101.5563

Multicomponent He I 10830 Å profiles in an active filament

C. Sasso·A. Lagg·S. K. Solanki
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Abstract

We present new spectropolarimetric observations of the chromospheric He I 10830 Å multiplet observed in a filament during its phase of activity. The data were recorded with the new Tenerife Infrared Polarimeter (TIP-II) at the German Vacuum Tower Telescope (VTT) on 2005 May 18. We inverted the He Stokes profiles using multiple atmospheric components. The observed He Stokes profiles display a remarkably wide variety of shapes. Most of the profiles show very broad Stokes I absorptions and complex and spatially variable Stokes V signatures. The inversion of the profiles shows evidence of different atmospheric blue- and redshifted components of the He I lines within the resolution element (1 arcsec), with supersonic velocities of up to 100 km/s. Up to five different atmospheric components are found in the same profile. We show that even these complex profiles can be reliably inverted.

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C. Sasso, A. Lagg, S. K. Solanki. 2011-01-28. Multicomponent He I 10830 Å profiles in an active filament. https://doi.org/10.1051/0004-6361%2F200912956

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