Importance of Angle-dependent Partial Frequency Redistribution in Hyperfine Structure Transitions Under the Incomplete Paschen-Back Effect Regime
Additional information
Authors
Nagendra K. N. .,
Sowmya K.,
Sampoorna M.,
Stenflo J. O.,
Anusha L. S. .
Type
Journal Article
Year
2020
Language
English
Abstract
Angle-frequency coupling in scattering of polarized light on atoms is represented by the angle-dependent (AD) partial frequency redistribution (PRD) matrices. There are several lines in the linearly polarized solar spectrum, for which PRD combined with quantum interference between hyperfine structure states play a significant role. Here we present the solution of the polarized line transfer equation including the AD-PRD matrix for scattering on a two-level atom with hyperfine structure splitting and an unpolarized lower level. We account for the effects of arbitrary magnetic fields (including the incomplete Paschen-Back effect regime) and elastic collisions. For exploratory purposes we consider a self-emitting isothermal planar atmosphere and use atomic parameters that represent an isolated Na I D$_2$ line. For this case we show that the AD- PRD effects are significant for field strengths below about 30 G, but that the computationally much less demanding approximation of angle-averaged PRD may be used for stronger fields.
Journal
Astrophysical Journal
Volume
898
Number
1
Start page number
49
Keywords
irsol-refereed-scientific-papers
