QCD corrections to the production of t(t)over-barγ at the ILC

A precise calculation of the top quark pair production associated with a hard photon is essential for testing the electroweak property of the top quark in the Standard Model (SM). We investigate the one-loop QCD corrections to the process e(+)e(-) -> t (t) over bar gamma at the International Linear Collider (ILC), and find that the K-factor can be as large as 1.238 (1.105, 1.060) for a center-of-mass energy root s = 500 (800, 1500) GeV. The transverse momentum distributions of the top quark and photon are respectively shown at leading order (LO) and next-to-leading order (NLO). Due to the asymmetric rapidity distribution of the top (anti-top) quark, we also study the top quark forward-backward asymmetry (A(FB)(t)) in try production at NLO, which is found to be 45.82 (55.25.55.89)% for root s = 500 (800, 1500) GeV. (C) 2011 Elsevier B.V. All rights reserved.