Test of the $X(3872)$ Structure in Antiproton-Nucleus Collisions

TL;DR

This paper proposes a novel experimental method to determine whether the $X(3872)$ particle is a molecular state by observing specific narrow peaks in antiproton-nucleus collision products.

Contribution

It introduces a new approach using two-step $ar D^*$ or $D$ production in $ar p A$ reactions to identify the molecular structure of $X(3872)$.

Findings

Narrow peaks in $ar D^*$ or $D$ distributions indicate molecular structure.

Method provides a clear experimental signature for $X(3872)$ composition.

Potential to resolve the nature of $X(3872)$ through collider experiments.

Abstract

The present day experimental data on the $X(3872)$ decays do not allow to make clear conclusions on the dominating structure of this state. We discuss here an alternative way to study its structure by means of the two-step $\bar D^*$ (or $D$) production in $\bar p A$ reactions. If this process is mediated by $X(3872)$, the characteristic narrow peaks of the $\bar D^*$ (or $D$) distributions in the light cone momentum fraction at small transverse momenta will appear. This would unambiguously signal the $D \bar D^*$ + c.c. molecular composition of the $X(3872)$ state.