Vol. 34, issue 07, article # 2

Kochanov V. P. Simplified theory of line broadening: dependence of spectral line parameters on speed and temperature. // Optika Atmosfery i Okeana. 2021. V. 34. No. 07. P. 488-501. DOI: 10.15372/AOO20210702 [in Russian].
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A simple version of the theory of line broadening is developed, which makes it possible to numerically and analytically calculate the parameters of collisional line broadening, shifting and narrowing of spectral lines based on the potentials of intermolecular interactions of the Lennard-Jones type. Namely, expressions are derived for the real and imaginary parts of the input and output frequencies of the collision integral, as well as for the line width. The main simplifications are in the model of non-degenerate states and one perturbing level. The eikonal approximation made it possible to express the constants under consideration in terms of the scattering S-matrices based on more general expressions in terms of the scattering amplitudes. The dependences of the considered parameters on the speed of active molecules and gas temperature are determined.


line broadening constants, interaction potential, scattering amplitudes


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