Top-quark pair production by electron–positron annihilation in a circularly polarized laser field

Abstract

In the framework of the electroweak standard model, we have investigated the top quarks pair production from e − e + annihilation at the energies of a future compact linear collider in the presence of an intense circularly polarized laser field. We have analytically generated the detailed expression for the laser-assisted differential cross section using the lowest-order Dirac-Volkov formalism, including the γ t t ˉ and Z t t ˉ interactions, in the center-of-mass frame. A wide range of center-of-mass energies corresponding to the future e − e + collider has been covered to study the behavior of the total cross section (TCS); this future compact linear collider constitutes an important direction in the study of top quark physics in order to improve the measurements, and the limits of some physical parameters obtained so far at the LHC and the Tevatron. We have analyzed the dependence of the laser-assisted total and partial cross sections on the energy of the center-of-mass of the colliding system e − e + and also on the parameters of the laser field, such as the number of exchanged photons, the laser field strength, and its frequency. The results indicate that the laser field decreases the order of magnitude of the TCS as much as the laser field strength increases or decreases its frequency.