|
Journal of Physical Studies 7(3), 357–364 (2003)
DOI: https://doi.org/10.30970/jps.07.357 THERMALIZATION OF THE RADIATION IN SUN SPOTS BY COLLISIONS WITH NEUTRAL HYDROGEN FOR NEUTRAL IRON LINESM. I. Stodilka
The Ivan Franko National University of Lviv,
Astronomical Observatory |
 |
We solved the multilevel non-LTE polarized radiation transfer problem for a sun spot. Two sun spot models are considered: a cool model (great spot), and a hot one (small spot). We studied an influence of collisions with neutral hydrogen atoms on Fe I levels populations, on unpolarized and polarized radiation in neutral iron lines. Neutral iron lines that arise in conditions of a small sun spot are faintly sensitive to collisions with hydrogen atoms. In a great spot collisions with hydrogen atoms thermalize radiation in the Fe I lines that are formed due to transitions between metastable, semistable-strongly excited levels and also in forbidden lines between metastable-semistable levels. With an increasing excitation potential of levels the sensitivity of lines to collisions with hydrogen atoms decreases. In compliance with NLTE studies it is necessary to take into account collisions with neutral hydrogen atoms that lead to the thermalization of the radiation in the sun spots.
PACS number(s): 95.30.Gv, 95.30.Jx, 96.60.Qc