Quantum theory of the Hanle effect. II - Effect of level-crossings and anti-level-crossings on the polarization of the D3 helium line of solar prominences
Résumé
In this paper, we present a generalization of the quantum formalism of the Hanle effect, including the case of level-crossings and anti-level-crossings of the Zeeman sublevels. The transition from the Zeeman effect to the Paschen-Back effect, which gives rise to the anti-level-crossings, is explicitly taken into account. As an application the calculation of the linear polarization parameters of the Helium D3 line of solar quiescent prominences, in the presence of a stationary magnetic field, has been performed. The results are reported and the effect of the level-crossings is discussed. These results extend our previous calculations which were valid only for weak magnetic fields (B < 10 G) because both the level-crossing and anti-level-crossing effects were neglected.