Semiexclusive production of $J/\psi$ mesons in proton-proton collisions with electromagnetic and diffractive dissociation of one of the protons

TL;DR

This paper calculates and compares the cross sections and distributions for electromagnetic and diffractive dissociation in semiexclusive $J/\psi$ production at the LHC, highlighting their similar magnitudes and providing detailed differential predictions.

Contribution

It provides the first detailed comparison of electromagnetic and diffractive dissociation contributions to semiexclusive $J/\psi$ production at the LHC, including differential distributions and cross section ratios.

Findings

Electromagnetic and diffractive dissociation cross sections are of similar magnitude.

Differential distributions vary with $J/\psi$ rapidity and dissociation type.

Predicted cross sections and distributions can guide experimental measurements.

Abstract

We calculate the cross sections for both electromagnetic and diffractive dissociation of protons for semiexclusive production of $J/\psi$ mesons in proton-proton collisions at the LHC. Several differential distributions in missing mass ($M_X$), or single-particle variables related exclusively to the $J/\psi$ meson are calculated for $\sqrt{s}$ = 7 TeV as an example. The cross sections and distributions are compared to the cross section of the purely exclusive reaction $p p \to p p J/\psi$. We show the corresponding ratio as a function of $J/\psi$ meson rapidity. We compare the distributions for purely electromagnetic and purely diffractive proton excitations/dissociation. We predict cross sections for electromagnetic and diffractive excitations of similar order of magnitude.