Predictions for diffraction at the LHC compared to experimental results

Abstract

Diffractive proton-proton cross sections at the lhc, as well as the total and total-inelastic proton-proton cross sections, are predicted in a simple model obeying all unitarity constraints. The model has been implemented in the pythia8-mbr event genera- tor for single diffraction, double diffraction, and central diffraction processes. Predictions of the model are compared to recent LHC results. The pythia8-mbr option includes a full simulation of the hadronization of the implemented diffrac- tion dissociation processes: single, double, and central diffraction. In the original mbr simulation used in cdf, the hadronization of the final state(s) was based on a data-driven phenomenological model of multiplicities and pt distributions calibrated using S ¯ ppS and Fermilab fixed-target results. Later, the model was successfully tested against Tevatron mb and diffraction data. However, only π ± and π 0 particles were produced in the final state, with multiplicities obeying a statistical model of a modified Gamma distribution function that provided good fits to experimental data (8). This model could not be used to predict specific-particle final states. In the pythia8-mbr implementation, hadronization is performed by PYTHIA8 tuned to reproduce final-state distributions in agreement with mbr's, with hadronization done in the pythia8 framework. Thus, all final-state particles are now automatically produced, greatly enhancing the horizon of applicability of tpythia8-mbr.