Production cross-section of antiprotons for the study of cosmic-ray propagation in the Galaxy

The production cross-section for antiprotons (p¯'s) in p-p collisions is presented for the study of cosmic-ray antiproton (CR-p¯) propagation in the Galaxy. We propose a semi-empirical production cross-section of p¯, with only three free parameters, the average multiplicity, Np¯, the average transverse momentum, 〈pT〉, and the deformation parameter, τ, which characterises the deformation from the isotropic angular distribution of p¯ in the center of mass system (CMS). This cross-section reproduces the experimental data now available in the proton projectile energy range of 10-1000 GeV very well. We also check the applicability of the present formula for proton-nucleus collisions. In order to apply the present result for the CR-p¯ data, we further present the energy dependence of the parameters appearing in the production cross-section of p¯.