Stopping Power V Linear Energy Transfer Let

STOPPING POWER refers to the inelastic energy losses by an electron moving through a medium with density r are described by the total mass–energy stopping power $\left ( \frac{S}{\rho} \right )_{tot}$, which represents the kinetic energy $E_K$ loss by the electron per unit path length x, or:

(1)
\begin{align} \left ( \frac{S}{\rho} \right )_{tot}= \frac{1}{\rho}.\frac{dE_K}{dx} (MeV.cm^2/g) \end{align}

$\left ( \frac{S}{\rho} \right )_{tot}$ consists of two components: the mass collision stopping power ($\left ( \frac{S}{\rho} \right )_{col}$), resulting from electron–orbital electron interactions (atomic excitations and ionizations), and the mass radiative stopping power ($\left ( \frac{S}{\rho} \right )_{rad}$), resulting from electron–nucleus interactions (bremsstrahlung production):