Survival probability of large rapidity gaps inp¯p, pp, γp,andγγcollisions

Abstract

Using an eikonal analysis, we simultaneously fit a QCD-inspired parametrization of all accelerator data on forward proton-proton and antiproton-proton scattering amplitudes, together with cosmic ray data (using Glauber theory), to predict proton-air and proton-proton cross sections at energies near $\sqrt{s}\ensuremath{\approx}30 \mathrm{TeV}.$ The p-air cosmic ray measurements greatly reduce the errors in the high energy proton-proton and proton-air cross section predictions---in turn, greatly reducing the errors in the fit parameters. From this analysis, we can then compute the survival probability of rapidity gaps in high energy $\overline{p}p$ and $\mathrm{pp}$ collisions, with high accuracy in a quasi-model-free environment. Using an additive quark model and vector meson dominance, we note that the survival probabilities are identical, at the same energy, for $\ensuremath{\gamma}p$ and $\ensuremath{\gamma}\ensuremath{\gamma}$ collisions, as well as for nucleon-nucleon collisions. Significantly, our analysis finds large values for gap survival probabilities: $\ensuremath{\approx}30%$ at $\sqrt{s}=200 \mathrm{GeV},$ $\ensuremath{\approx}21%$ at $\sqrt{s}=1.8 \mathrm{TeV}$ and $\ensuremath{\approx}13%$ at $\sqrt{s}=14 \mathrm{TeV}.$