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

The littlest Higgs model with discrete symmetry named “T-parity” (LHT) is an interesting new physics model which does not suffer strong constraints from electroweak precision data. One of the important features of the LHT model is the existence of new source of FC interactions between the SM fermions and the mirror fermions. These FC interactions can make significant loop-level contributions to the couplings tcV  , and furthermore enhance the cross sections of the FC single-top quark production processes. In this paper, we study some FC single-top quark production processes, pp→tc¯ and pp→tVpp→tV, at the LHC in the LHT model. We find that the cross sections of these processes strongly depend on the mirror quark masses. The processes pp→tc¯ and pp→tgpp→tg have large cross sections with heavy mirror quarks. The observation of these FC processes at the LHC is certainly the clue of new physics, and further precise measurements of the cross sections can provide useful information about the free parameters in the LHT model, specially about the mirror quark masses.