Experimental and theoretical study of the energy loss of C and O in Zn

E. D. CANTERO; C. C. MONTANARI; M. BEHAR; R. C. FADANELLI; G. H. LANTSCHNER; J. E. MIRAGLIA; N. R. ARISTA

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Año: 2011

1050-2947

We present a combined experimental-theoretical study of the energy loss of C and O ions in Zn in the energy range of 50-1000 keV/amu. This contribution has a double purpose, on the experimental side, we present stopping power measurements that fill a gap in the literature for these projectile-target combination and covers an extended energy range including the stopping maximum. On the theoretical side, we make a quantitative test on the applicability of various theoretical approaches to calculate the energy loss of heavy swift ions in solids. The description is performed using different models for valence and inner-shell electrons: a non-perturbative scattering calculation based on the Transport Cross Section formalism (TCS) to describe Zn valence electron contribution, and two different models for the inner-shell contribution: the Shellwise Local Plasma Approximation (SLPA) and the Convolution approximation for swift Particles (CasP). The new experimental results indicate that C is the limit for the applicability of the SLPA approach, which previously was successfully applied to projectiles from H to B. We find that this model clearly overestimates the stopping data for O ions. The origin of these discrepancies is related to the perturbative approximation involved in the SLPA. This shortcoming has been solved by using the non-perturbative CasP results to describe the inner-shell contribution, which yields a very good agreement with the experiments for both C and O ions.