Evidence for rapidly rising ρ-ρ total cross section from cosmic-ray data

Abstract

We give estimates of lower bounds on the ρ-ρ total cross section based on cosmic-ray data. We find that σ_pp rises at least as rapidly as 38.8+0.4ln²(s/s₀) from E˜10³ to 3×10⁴ GeV incident energy, corresponding to σ_pp»60 mb at the highest energy available. In view of large experimental errors at the highest energies, a value of σ_pp»48 mb can be estimated at 95% confidence level at E∼10⁴ GeV.