The real part of the pp amplitude and rising cross sections

Abstract The new experimental evidence of a rising pp total cross section ( σ pp ) makes it necessary to recalculate the real part of the forward scattering amplitude, which previously has been calculated assuming σ pp → constant asymptotically. In this paper the results of dispersion relations calculations of the real part at all energies are presented, with various assumptions about the asymptotic behaviour of both σ pp and σ p p , consistent with the latest experimental data.