Multicomponent He I 10 830 Å profiles in an active filament

¹ Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, Katlenburg-Lindau, Germany
e-mail: csasso@oacn.inaf.it
² INAF – Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, 80131 Napoli, Italy
³ School of Space Research, Kyung Hee University, Yongin, 446-701 Gyeonggi, Korea

Received: 22 July 2009
Accepted: 27 September 2010

Abstract

Aims. We present new spectropolarimetric observations of the chromospheric He i 10 830 Å multiplet observed in a filament during its phase of activity.

Methods. 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.

Results. 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^-1. Up to five different atmospheric components are found in the same profile. We show that even these complex profiles can be reliably inverted.