Production of the X(3872) at the Tevatron and the LHC

TL;DR

This paper predicts the production rates of the X(3872) particle at the Tevatron and LHC using QCD calculations, addressing previous discrepancies and supporting its interpretation as a weakly-bound charm-meson molecule.

Contribution

It provides a detailed theoretical prediction of X(3872) production cross sections incorporating NRQCD and rescattering effects, clarifying previous conflicting analyses.

Findings

Predicted cross sections align with experimental data for high transverse momentum.

Rescattering effects significantly increase the upper bound of production rates.

Supports the interpretation of X(3872) as a weakly-bound charm-meson molecule.

Abstract

We predict the differential cross sections for production of the X(3872) at the Tevatron and the Large Hadron Collider from both prompt QCD mechanisms and from decays of b hadrons. The prompt cross section is calculated using the NRQCD factorization formula. Simplifying assumptions are used to reduce the nonperturbative parameters to a single NRQCD matrix element that is determined from an estimate of the prompt cross section at the Tevatron. For X(3872) with transverse momenta greater than about 4 GeV, the predicted cross section is insensitive to the simplifying assumptions. We also discuss critically a recent analysis that concluded that the prompt production rate at the Tevatron is too large by orders of magnitude for the X(3872) to be a weakly-bound charm-meson molecule. We point out that if charm-meson rescattering is properly taken into account, the upper bound is increased by orders of magnitude and is compatible with the observed production rate at the Tevatron.