Line Broadening

Abstract

The shapes of lines are described by line shape functions {\textbackslash}({\textbackslash}mathcal{L\}{\textbackslash}) in frequency ν, angular frequency ω, wavelength λ, or wavenumber units σ. In theoretical calculations the angular frequency ω is usually preferred. {\textbackslash}({\textbackslash}mathcal{L\}{\textbackslash}) is normalized: $\${\textbackslash}int_{\{{\textbackslash}rm line}} {\textbackslash}mathcal{L} {\textbackslash}left({\textbackslash}omega{\textbackslash}right) \{{\textbackslash}rm d\}{\textbackslash},{\textbackslash}omega = 1.$$ (9.1) Naturally, experimental profiles are given as function of wavelength or wavenumber. When converting into wavelength, the wavelength factor results in an inherent asymmetry of a profile which is symmetric in ω: