Energy Loss Expressed in Universal Constants

The most interesting feature of the work of Lindhard et al. is the possibility of expressing the electronic and the nuclear stopping power in terms of universal constants, a form independent of the mass and charge of the individual atoms. A universal energy e and a universal range p are defined, and the energy loss is expressed in terms 

The nuclear energy loss is related to the stopping cross section a by 

R is the normal range of the projectile in matter and N is the number of stopping atoms per unit volume. 

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