Study of the single neutral top-pion production process at $γγ$ collider

Abstract

$γγ\to Π_t^0$ is the major production mechanism of neutral top-pion at the linear colliders. In this paper, we calculate the cross section of the process $γγ\to Π^0_t$ and discuss the potential to observe the neutral top-pion via its various decay modes at the planned ILC. The study show that, among the various neutral top-pion production processes at the linear colliders, the cross section of $γγ\to Π_t^0$ is the largest one which can reach the level of $10^1-10^2$ fb. Due to the existence of the tree-level flavor-changing coupling $Π_t^0 t\bar{c}$, $γγ\to Π_t^0 \to t\bar{c}$ can provide enough number of typical signals to identify the neutral top-pion with the clean SM background. Therefore, the process $γγ\to Π_t^0$ play an important role in searching for the neutral top-pion and test the TC2 model.