Equation 9.11.617B4446B6082E

\begin{equation} P_\gamma (t)= \begin{cases} \displaystyle \frac{4\pi C_0}{V(\gamma -1)(\gamma -2)} t^{2-\gamma },& \gamma \ne 2,\\[4pt] \displaystyle -\frac{4\pi C_0}{V}\log t,& \gamma =2. \end{cases} \end{equation}