The flavor-changing top-charm quark production in the littlest Higgs model with T-parity at the ILC

With high luminosity and energy at the ILC and clean SM backgrounds, the top-charm production at the ILC should have powerful potential to probe New Physics. The littlest Higgs model with discrete symmetry named “T-parity” (LHT) is one of the most promising New Physics models. In this paper, we study the FC top-charm quark production processes e+e−(γγ)→tc¯ at the ILC in the LHT model. Our study shows that the LHT model can make a significant contribution to these processes. When the masses of mirror quarks become large, these two processes are accessible at the ILC. So the top-charm production at the ILC provides a unique way to study the properties of the FC couplings in the LHT model. On the other hand, we make a comparison among various New Physics models and find that the cross sections of e+e−(γγ)→tc¯ in the LHT model are significantly larger than those in other New Physics models. So the processes e+e−(γγ)→tc¯ may also provide a way to distinguish the LHT model from the others.