Formula_12945

\[\begin{gathered}\sigma^{\mathrm{y} \Pi \mathrm{p}}=\sum_{l=0}^{\infty} \sigma_{l}^{\mathrm{y} п \mathrm{p}}, \\\sigma_{l}^{\mathrm{y} \Pi \mathrm{p}}=\pi \lambda^{2}(2 l+1)\left|S_{l}-1\right|^{2},\end{gathered}\]