Probing the anomalous tq gamma couplings through single top production at the future lepton-hadron colliders

摘要

The measurements of the top quark flavor changing neutral current interactions are one of the most important goals of the top quark physics program in the present and the future collider experiments. These measurements provide direct information on nonstandard interactions of the top quark. Within the framework of new physics beyond the Standard Model, these interactions can be defined by an effective Lagrangian. In this study, we have investigated the potential of the future mu p colliders on the top quark flavor changing neutral current interactions through the subprocesses gamma q -> t -> Wb, where q = u, c. These subprocesses have been produced through the main reaction mu p -> mu gamma p -> mu WbX at the LHC-mu p, the FCC-mu p and the SPPC-mu p. For the main reaction, the total cross-sections have been calculated as a function of the anomalous tq gamma couplings. In addition, sensitivities on BR(t -> q gamma) at 95% Confidence Level have been calculated. We obtain that the best constraints on BR(t -> q gamma) are at the order of 10(-7) which is four orders of magnitude better than the LHC's experimental results.