Linear polarization of the λ1031.92 coronal line

II. Constraints on the magnetic field and the solar wind velocity field vectors in the coronal polar holes

¹ Max-Planck-Institut für Aeronomie, Max-Planck-Str. 2, 37191 Katlenburg-Lindau, Germany
² Laboratoire d'Étude du Rayonnement et de la Matière en Astrophysique (LERMA), Observatoire de Paris-Meudon, 92195 Meudon, France
³ Institut d'Astrophysique Spatiale, Université Paris XI, 91405 Orsay Cedex, France

Corresponding author: N.-E. Raouafi, Raouafi@linmpi.mpg.de

Received: 2 May 2002
Accepted: 25 September 2002

Abstract

Numerical computation results of the linear polarization parameters of the   coronal line are presented. They are based on theoretical results obtained by Raouafi (2002 and 2000), which give the Stokes parameters of a resonance scattering spectral line sensitive simultaneously to the Hanle effect and to the Doppler redistribution. In the present coronal case, the Hanle effect is due to the coronal magnetic field and the Doppler redistribution to the macroscopic motion of the scattering O⁵⁺ coronal ions (solar wind velocity field vector). Constraints on the coronal magnetic field vector and on the solar wind velocity field vector are obtained by comparing the numerical results and the linear polarization measurements of the   coronal line obtained through particular observations performed by SUMER/SoHO.