Structure and production mechanism of the enigmatic $X(3872)$ in high-energy hadronic reactions

TL;DR

This paper investigates the production mechanisms of the enigmatic X(3872) particle in high-energy hadronic reactions, comparing charmonium and molecular models, and includes both single and double parton scattering contributions.

Contribution

It provides a detailed calculation of X(3872) production cross sections considering multiple scenarios and scattering processes, aligning theoretical models with experimental data.

Findings

Both charmonium and molecular models can explain observed cross sections.

Double parton scattering contributes less than single parton scattering.

Upper limits for DPS production are below CMS measurements.

Abstract

We calculate the total cross section and transverse momentum distributions for the production of enigmatic $\chi_{c,1}(3872)$ (or X(3872)) assuming different scenarios: $c \bar c$ state and $D^{0*} {\bar D}^0 + D^0 {\bar D}^{0*}$ molecule. The derivative of the $c \bar c$ wave function needed in the first scenario is taken from a potential model calculations. Compared to earlier calculation of molecular state we include not only single parton scattering (SPS) but also double parton scattering (DPS) contributions. The latter one seems to give smaller contribution than the SPS one. The upper limit for the DPS production of $\chi_{c,1}(3872)$ is much below the CMS data. We compare results of our calculations with existing experimental data of CMS, ATLAS and LHCb collaborations. Reasonable cross sections can be obtained in either $c \bar c$ or molecular $D {\bar D}^*$ scenarios for $X(3872)$. Also a hybrid scenario is not excluded.