Colour and baryon number fluctuation of preconfinement system in production process and T_cc structure

TL;DR

This paper investigates the production mechanisms of the T_cc^+ resonance, proposing that its structure can be distinguished as a four-quark state or a hadron molecule through specific experimental signatures, with current data favoring a four-quark configuration.

Contribution

It introduces a method to differentiate T_cc^+ structure by analyzing production properties and correlations, highlighting the role of colour connections in production mechanisms.

Findings

Data favors a four-quark state production via cc diquark fragmentation.

Measurement of momentum correlation of DD* can distinguish the structure.

Production properties reflect the underlying quark configuration.

Abstract

We suggest to study the production mechanism and some details of the production properties to probe the structure of the DDpi resonance T_cc^+ recently observed by the LHCb Collaboration. If the resonance is produced as a four-quark state, one can find the corresponding finger prints via measurements on some production properties that are the same as those of Xi_cc. The reason is that a special colour connection on the interface between the perturbative and non perturbative QCD is required for these doubly-charm hadron production. On the other hand, if T_cc^+ is produced as a hadron molecule, the measurement on the momentum correlation of DD^* can be a smoking gun to make the judgement. The present data favour a compact four-quark state production via the cc diquark fragmentation.