Shedding light on the $t\bar{t}$ asymmetry: the photon handle

Abstract

We investigate a charge asymmetry in $t\bar{t}\gamma$ production at the LHC that provides complementary information to the measured asymmetries in $t\bar{t}$ production. We estimate the experimental uncertainty in its measurement at the LHC with 8 and 14 TeV. For new physics models that simultaneously reproduce the asymmetry excess in $t\bar{t}$ at the Tevatron and the SM-like asymmetry at the LHC, the measurement in $t\bar{t}\gamma$ at the LHC could exhibit significant deviations with respect to the SM prediction.

Comments: LaTeX 15 pages