Production cross sections of cosmic antiprotons in the light of new data from the NA61 and LHCb experiments

Abstract

The cosmic-ray flux of antiprotons is measured with unprecedented precision by the particle spectrometer AMS-02 on the International Space Station. Its interpretation requires a correct description of the dominant production process for antiprotons in our Galaxy, namely, the interaction of cosmic-ray proton and helium with the atoms of the interstellar medium. In light of new cross section measurements by the NA61 experiment of $p + p \rightarrow \pbar + X$ and the first ever measurement of $p + \mathrm{He} \rightarrow \pbar + X$ by the LHCb experiment in a fixed target configuration, we update the parametrization of proton-proton and proton-nucleon cross sections and their uncertainties. The new parametrizations for the cross section are used to derive the total source term of secondary antiprotons. Since uncertainties, in particular at low energies, are significantly larger than those on the measured antiproton flux by the AMS-02 experiment, we finally quantify the necessity of new data on antiproton production cross sections, and pin down the kinematic parameter space which should be covered by future high-energy experiments.