An alternative way to decipher the nature of the doubly charmed tetraquark $T_{cc}(3875)^+$: its antiparticle $T_{{\bar c}{\bar c}}(3875)^-$ photoproduction off nuclei near threshold

TL;DR

This paper investigates the photoproduction of doubly charmed tetraquark antiparticles near threshold energies to determine their internal structure, using theoretical models and proposing experimental measurements at future colliders.

Contribution

It introduces a novel approach to decipher the internal structure of $T_{cc}(3875)^+$ tetraquarks via photoproduction observables near threshold energies.

Findings

Sensitivity of observables to different internal structure scenarios.

Potential to clarify tetraquark structure through future collider experiments.

Calculated cross sections and ratios for various target nuclei and energies.

Abstract

We study the inclusive photoproduction of $T_{{\bar c}{\bar c}}(3875)^-$ mesons (which are the antiparticles of the doubly charmed tetraquarks $T_{cc}(3875)^+$ discovered recently by the LHCb Collaboration) from nuclei in the near-threshold energy region within the nuclear spectral function approach by considering incoherent direct (${\gamma}p(n) \to D^+(D^0){T_{{\bar c}{\bar c}}(3875)^-}\Lambda^+_c$) photon--nucleon $T_{{\bar c}{\bar c}}(3875)^-$ creation processes as well as five possible different scenarios for their internal structure with the main goal of clarifying the possibility to decipher this structure (and, hence, that of $T_{cc}(3875)^+$) in photoproduction via integral and differential observables. We calculate the absolute and relative excitation functions for $T_{{\bar c}{\bar c}}(3875)^-$ production off $^{12}$C and $^{184}$W target nuclei at near-threshold photon beam energies of 30--38 GeV, the absolute differential cross sections for their production off these target nuclei at laboratory polar angles of 0$^{\circ}$--10$^{\circ}$ as well as the A and momentum dependences of the relative (transparency ratios) cross sections for $T_{{\bar c}{\bar c}}(3875)^-$ production at photon energy of 35 GeV within the adopted scenarios for the $T_{{\bar c}{\bar c}}(3875)^-$ meson intrinsic structure. We demonstrate that the absolute and relative observables considered show a certain sensitivity to these scenarios. Therefore, the measurement of such observables in future experiments at the proposed high-luminosity electron-ion colliders EIC and EicC in the US and China in the near-threshold energy region might shed light on the $T_{cc}(3875)^+$ internal structure.