Production of doubly charmed tetraquark $T_{cc}$ via photon-photon fusion at electron-positron colliders

Abstract

Within a phenomenological diquark fragmentation model, we study the production of doubly charmed tetraquark $T_{cc}$ via photon-photon fusion at electron-positron colliders. The production of $T_{cc}$ is divided into two steps: the perturbative production of heavy $(cc)$-diquark and its nonperturbative hadronization. Two diquark configurations of $(cc)[^3S_1]_{\bar{3}}$ and $(cc)[^1S_0]_{6}$ are considered, and the $(cc)[^3S_1]_{\bar{3}}$ state dominates the produciotn of $T_{cc}$. We discuss two hadronization models of $(cc)[^3S_1]_{\bar{3}}$ intermediate state into the tetraquark $T_{cc}$. It is found that it is promising to observe the tetraquark $T_{cc}$ via photon-photon fusion process both at the Circular Electron Positron Collider (CEPC) and the International Linear Collider (ILC). We find that the cross sections are sensitive to constituent charm quark mass of diquark, and they also have strong dependence on the hadronization models.