# Nuclear transparency

If the nuclear cross-section is denoted as $\sigma_N$ and free nucleon cross-section as $\sigma_0$ then nuclear transparency can be defined as
$T= \sigma_N/A\sigma_0$, where $\sigma_N$ can be parameterized in terms of $\sigma_0$ as $\sigma_N =A^\alpha \sigma_0$.
Therefore, transparency can be expressed as $T= A^{\alpha -1}$.