Analytic amplitudes for hadronic forward scattering: COMPETE update

We consider several classes of analytic parametrizations of hadronic scattering amplitudes, and compare their predictions to all available forward data (pp, p-bar p, πp, Kp, γp, γγ, Σp). Although these parametrizations are very close for √s ≥ 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term ∼ ln2 s enables one to extend the fit down to √s = 4 GeV. We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude (ρ parameter) for present and future pp and p-bar p colliders, and on the total cross sections for γp → hadrons at cosmic-ray energies and for γγ → hadrons up to √s = 1 TeV