The capability of the LHC to study the electromagnetic dipole moments of the top quark is discussed. In particular, the process $pp\to p\gamma \gamma p\to pt\overline{t}p$, which is supposed to be tagged by the forward/backward detectors at the LHC experiments, is used to explore the top quark electric and magnetic moments. We perform analytical calculations and then a numerical analysis on the sensitivity of the total cross section of the top quark pair production in $\gamma \gamma$ scattering at the LHC to the anomalous top quark couplings with photon. It is shown that improvements in the bounds on the electromagnetic dipole moments of the top quark can be achieved in this channel in comparison with the constraints from the former studies.

• Received 29 April 2015

DOI:https://doi.org/10.1103/PhysRevD.92.014006