Stopping power of solids in planar channelling

In order to find the effects of extended defects (like dislocations) on the energy loss rate of charged particles in channelling one needs to know the position dependence of the stopping power in the channels. The variations of the stopping power Se for MeV α‐particles with position in (111) and (100) planar channels of gold, silver, and copper single crystals are calculated. The effective electron density responsible for stopping in planar channelling is calculated by taking suitable planar average of density due to different shells of individual atoms in the plane. The results are compared with available experimental data for gold. The energy dependence of stopping power for well channelled α‐particles in Au(111) planar channels in the energy range 1 to 5 MeV is found to follow an empirical relation Se∼E−3/4. The dependence of energy loss on the oscillation amplitude in Au(111) channels is also calculated and compared with available experimental data and good agreement is found.