Production of $\chi_c$- and $\chi_b$-mesons in high energy hadronic collisions

TL;DR

This paper investigates the production mechanisms of $$- and $$-mesons in high energy hadronic collisions using NRQCD, analyzing experimental data to extract non-perturbative matrix elements and understanding the role of color singlet and octet contributions.

Contribution

It provides a phenomenological analysis of $$-mesons production, extracting NRQCD matrix elements, and offers predictions for $$-meson cross sections based on scaling rules.

Findings

The $p_T$-spectrum of $$-mesons is mainly formed by color singlet components.

The $_2/_1$ ratio depends strongly on color octet matrix elements.

Predictions for $$-meson cross sections are provided using NRQCD scaling rules.

Abstract

This paper is devoted to phenomenological study of $\chi_{c,b}$-mesons production in high energy hadronic collisions in the framework of NRQCD. We analyze all available experimental data on $\chi_c$-mesons production and extract non-perturbative NRQCD matrix elements from fitting the data. We show, that measured $p_T$-spectrum of $\chi_c$-mesons is mainly formed by color singlet components, while $\sigma(\chi_{c2})/\sigma(\chi_{c1})$ ratio depends strongly on color octet matrix elements; this ratio becomes a highly sensitive tool to study contribution of different terms from the NRQCD expansion. Obtained using NRQCD scaling rules predictions for $\chi_b$-mesons cross sections are also given.