Full $mathcal{O}(alpha)$ electroweak radiative corrections to $e^+e^- rightarrow t bar{t} gamma$ with GRACE-Loop


Abstract in English

We present the full $mathcal{O}(alpha)$ electroweak radiative corrections to the process $e^+e^- rightarrow t bar{t} gamma$ at the International Linear Collider (ILC). The computation is performed with the help of the GRACE-Loop system. We present the total cross-section and the top quark forward-backward asymmetry ($A_{FB}$) as a function of the center-of-mass energy and compare them with the process $e^+e^- rightarrow t bar{t}$. We find that the value of $A_{FB}$ in $t bar{t} gamma$ production is larger than $A_{FB}$ in $tbar{t}$ production. It is an important result for the measurement of the top quark forward-backward asymmetry at the ILC. Applying a structure function method, we also subtract the QED correction to gain the genuine weak correction in both the $alpha$ scheme and the $G_{mu}$ scheme ($delta_{W}^{G_{mu}}$). We obtain numerical values for $delta_{W}^{G_{mu}}$ which are changing from 2% to -24% when we vary the center-of-mass energy from 360 GeV to 1 TeV.

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