World data of J/psi production consolidate NRQCD factorization at NLO

TL;DR

This paper performs a comprehensive NLO analysis of J/psi production across multiple experimental settings using NRQCD, confirming the universality of long-distance matrix elements with extensive data fitting.

Contribution

It provides the first global NLO fit of CO LDMEs for J/psi production across diverse processes, consolidating NRQCD factorization validity.

Findings

Successful simultaneous fit to 194 data points from various colliders.

Validation of NRQCD universality for CO LDMEs across different production mechanisms.

Enhanced understanding of relativistic corrections in J/psi production.

Abstract

We calculate the cross sections of inclusive J/psi production in photoproduction and two-photon scattering, involving both direct and resolved photons, and in e^+e^- annihilation at next-to-leading order (NLO) within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), including the full relativistic corrections due to the intermediate ^1S_0^{[8]}, ^3S_1^{[8]}, and ^3P_J^{[8]} color-octet (CO) states. Exploiting also our previous results on hadroproduction, we perform a combined fit of the respective CO long-distance matrix elements (LDMEs) to all available high-quality data of inclusive J/psi production, from KEKB, LEP~II, RHIC, HERA, the Tevatron, and the LHC, comprising a total of 194 data points from 26 data sets.