Polarization in spectral lines

✍ Scribed by E. Landi Degl'Innocenti

• Book ID: 104645521
• Publisher: Springer
• Year: 1985
• Tongue: English
• Weight: 894 KB
• Volume: 102
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00154032

✦ Synopsis

The general formalism presented in a previous paper of this series (Landi Degl'Innocenti, 1983a) is particularized to deduce the radiative transfer equations for polarized radiation and the statistical equilibrium equations for a multi-level atom in the Hanle effect, collisionless regime. The formulae are developed both in the standard representation and in the representation of the statistical tensors. For resonance scattering in a two-level atom in the presence of a weak magnetic field, in the limiting case of complete depolarization of the ground level, we recover the classical results of the Hanle effect and we derive the expression of the phase matrix in terms of ordinary rotation matrices. A magnetic kernel is introduced in the formalism and its main properties are analyzed. In particular, an expression for the magnetic kernel is derived for a turbulent magnetic field and the corresponding phase matrix is evaluated. Finally, the law of scattering is generalized to take properly into account the influence of the anisotropy of the radiation field on the atomic polarization of the ground level (depopulation pumping in the Hanle effect).

HA loOM) = (Eoa + hVLg~M) IoalM) ,

(2) * From now on, we will refer to Equation (n) of Paper N with the symbol (n; N).