Detection of chromospheric magnetic fields: a forward modeling approach .
Abstract
We show that circular and linear polarization in chromospheric spectral lines, in particular that resulting from the Zeeman effect, is generally expected to be small because these lines form at high temperatures and arise from light elements. To illustrate these points we solve two-dimensional non-LTE radiative transfer in the Ca II 854.21 nm line through a magnetostatic flux concentration model and calculate the expected polarization. Finally, we show that the vertical magnetic field on the axis of the concentration can be recovered by measuring the bisector separation of the left- and right-hand circularly polarized emergent profiles.
- Publication:
-
Memorie della Societa Astronomica Italiana
- Pub Date:
- 2010
- Bibcode:
- 2010MmSAI..81..701U
- Keywords:
-
- Sun: chromosphere;
- magnetic fields;
- line: profiles;
- radiative transfer;
- polarization