Production cross sections of γ-rays, electrons, and positrons in p–p collisions

Abstract

Because the production cross sections of γ rays, electrons, and positrons (e ± ) made in p-p collisions, σ pp→γ and σ pp→e ± , respectively, are kinematically equivalent with respect to the parent pion-production cross section σ pp→π , we obtain σ pp→e ± directly from the machine data on σ pp→γ . In Paper I (Sato et al.[1]), we give explicitly σ pp→γ , reproducing quite well the accelerator data with LHC, namely σ pp→e ± is applicable enough over the wide energy range from GeV to 20 PeV for projectile proton energy. We dicuss in detail the relation between the cross sections, and present explicitly σ pp→e ± that are valid into the PeV electron energy.

LOCAL H i EMISSIVITY MEASURED WITHFERMI-LAT AND IMPLICATIONS FOR COSMIC-RAY SPECTRA

“…The approach chosen by Shibata et al (2014) is different and based only on γ-ray production cross-sections obtained in p-p collisions spanning the range of energies from the threshold pion production to energies of the Large Hadron Collider experiments. The cross-section is parametrized with an empirical formula depending on the γ-ray energy and transverse momentum as well as four physical parameters that are adjusted so that the empirical cross-section and deduced quantities fit the experimental data (Shibata et al 2013;Sato et al 2012;Shibata et al 2007;Suzuki et al 2005).…”