Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-10-04
Astrophys.J.655:642-650,2007
Astronomy and Astrophysics
Astrophysics
Accepted for publication in The Astrophysical Journal (It is tentatively scheduled for the ApJ January 20, 2007 issue)
Scientific paper
10.1086/509795
The polarization observed in the spectral lines of the He I 10830 multiplet carries valuable information on the dynamical and magnetic properties of plasma structures in the solar chromosphere and corona, such as spicules, prominences, filaments, emerging magnetic flux regions, etc. Here we investigate the influence of atomic level polarization on the emergent Stokes profiles for a broad range of magnetic field strengths, in both 90 degree and forward scattering geometry. We show that, contrary to a widespread belief, the selective emission and absorption processes caused by the presence of atomic level polarization may have an important influence on the emergent linear polarization, even for magnetic field strengths as large as 1000 G. Consequently, the modeling of the Stokes Q and U profiles should not be done by taking only into account the contribution of the transverse Zeeman effect within the framework of the Paschen-Back effect theory, unless the magnetic field intensity of the observed plasma structure is sensibly larger than 1000 G. We point out also that in low-lying optically thick plasma structures, such as those of active region filaments, the (horizontal) radiation field generated by the structure itself may substantially reduce the positive contribution to the anisotropy factor caused by the (vertical) radiation field coming from the underlying solar photosphere, so that the amount of atomic level polarization may turn out to be negligible. Only under such circumstances may the emergent linear polarization of the He I 10830 multiplet in such regions of the solar atmosphere be dominated by the contribution caused by the transverse Zeeman effect.
Asensio Ramos Andrés
Trujillo Bueno Javier
No associations
LandOfFree
Influence of atomic polarization and horizontal illumination on the Stokes profiles of the He I 10830 multiplet does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Influence of atomic polarization and horizontal illumination on the Stokes profiles of the He I 10830 multiplet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Influence of atomic polarization and horizontal illumination on the Stokes profiles of the He I 10830 multiplet will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-655381