الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
The physical properties of an ionized plasma of the solar corona and chromosphere can be understood best from an interpretation of its emission-like spectrum, which is produced mainly by electron impact excitation of positive ions. Excitation of coronal ions takes place by thermal processes such as collisional excitations of metastable and normal levels of highly ionized ions, collisional ionization, and cascade and radiative excitation of coronal lines. The complete and systematic study of the emission-like spectrum determines, in principle, the chemical composition of various elements and their density and temperature, and hence, an estimate of the amount of far-ultraviolet radiation emitted by the Sun and the energy balance in the solar corona and chromosphere.