Optics and Spectroscopy, 2020 Volume 128, Issue 10,Pages 1518–1524(Mi os285)
Laser physics and laser optics
Influence of uncertainty of spontaneous emission probabilities on the temperature dependence of collisional self-broadened coefficients of spectral lines of CO$_2$ molecules
Abstract:
The influence of the deviation of the spontaneous radiation probability of the spectral lines of CO$_2$$A$ on the temperature dependence of the collisional self-broadened coefficients $\gamma$ in solving the inverse problem of joint determination of $A$ and $\gamma$ from the array of absorption coefficients is studied. The study was carried out for two cases: 1) $A$ = 0.2022 s$^{-1}$ (HITRAN2012); 2) the values of $A$ were obtained by minimizing the sum of weighted squares of the absorption coefficients differences. It was found that in the temperature range of 300–700 K, when the absorption coefficients are measured with accuracy 0.05$\alpha_{\operatorname{min}}$, the deviation of the functions $\gamma(T)$ does not exceed 5%. There is no causal relationship between the parameters $\gamma$ and $A$. The method of least squares allows us to correctly calculate the temperature dependences of the collisional self-broadened coefficients of the CO$_2$ lines $\gamma(T)$.
Keywords:carbon dioxide, self-broadened collisional coefficient, probability of spontaneous emission, correlation.