Measurement of the Cross Section for $\text{tt}\gamma$ Production in pp Collisions at $\sqrt{s}$ = 13 TeV with CMS

The production of a top quark pair with a photon is sensitive to beyond the standard model physics such as a top quark electric dipole, or top quark production charge asymmetry. We report the cross section for the production of a top quark pair with a photon $\sigma(\text{tt}\gamma)$, and the ratio of cross sections $\sigma(\text{tt}\gamma)$/$\sigma(\text{tt})$ using the Run 2 data of the CMS experiment. The analysis is carried out in the semileptonic electron and muon decay channel. Backgrounds are constrained by extensive studies in control regions.