Pion production momentum loss of cosmic ray hadrons

We present new results on the energy loss rate of high energy protons due to pion production in proton–proton interactions. Our calculations are based on the parameterized pion flux of Kelner et al. Our new results are valid for proton energies in the range of 1 GeV $\ll E⩽{10}^8$ GeV, which enhance the valid energy range by orders of magnitude. With these results one can calculate the energy loss due to pion production for cosmic ray protons from low energies to energies between the knee and ankle.