Calculations on vicinage effects in the energy loss of fast Bn+ (n=2,3,4) molecules in carbon foils

Abstract

We have evaluated the vicinage effects in the energy loss of the boron fragments resulting from the dissociation of fast Bn+ (n=2,3,4) molecular ions when traversing amorphous carbon foils. We obtain the stopping power ratio as a function of the foil thickness, taking into account the Coulomb explosion among the n fragments of the Bn+ source ion and using the dielectric formalism to describe the electronic excitations produced in the target by the boron fragments. Our results show that the vicinage effects increase with the projectile energy and with the number of molecular constituents, which agree satisfactorily well with the experimental data.