Diffractive photoproduction of Z^0 bosons in coherent interactions at CERN-LHC

TL;DR

This paper estimates the cross sections and rapidity distributions for exclusive Z^0 boson photoproduction in high-energy hadron collisions at CERN-LHC, using the color dipole formalism, providing the first such theoretical predictions.

Contribution

It extends the color dipole formalism to include Z^0 boson production in coherent hadron collisions, offering the first theoretical estimates for this process at collider energies.

Findings

Feasible Z^0 production analysis in pp collisions.

First estimation of Z^0 photoproduction cross sections in this context.

Limited prospects for observing in AA collisions.

Abstract

The exclusive $Z^0$ photoproduction at high energies in $\gamma p (A)$, $p p$ and $AA$ collisions is investigate within the color dipole formalism. We generalize the description of the deeply virtual compton scattering (DVCS) process, which describe quite well the HERA data, for the production of $Z^0$ bosons and estimate the total cross section for the exclusive process $\gamma^* h\to Z^0 h$ ($h=p,A$) for different energies, photon virtualities and atomic numbers. As hadrons at collider energies are a source of Weizs\"{a}cker - Williams photons, we consider electromagnetic interactions in hadron-hadron collisions at Tevatron and LHC energies and estimate the rapidity distribution and total cross section for $Z^0$ production in the $h h\to h Z^0 h$ process. This is the first estimation for such a process in literature. It can allow us to study, for instance, the physics of hadronic $Z^0$ decays in a clean environment characterized by two rapidity gaps. Our results indicate that the experimental analyzes of this process could be feasible in $pp$ but the physics scenario for $AA$ collisions is not promising.