Stopping power of protons in He at low energies

(Received 30 December 1991, revised 8 April 1992, accepted 1 June 1992)

Abstract
Using the Scattering Approach for Stopping in an Electron Gas, the Local Density Approximation (LDA), an adiabatic criterion, and capture and loss contributions to the electronic energy loss we have calculated the electronic stopping power of protons in helium and hydrogen gases at low energies. The combined model used give a significant deviation from the well known velocity proportionality of the stopping power at very low energy in the two cases. Our calculations explain quite well this striking deviation reported in recent papers. A good agreement is obtained with experimental values in case of He.