We provide and discuss the precision predictions for the W + W − γ production at the ILC including the full electroweak (EW) one-loop corrections and high order initial state radiation (ISR) contributions in the standard model. The dependence of the leading order (LO) and EW corrected cross sections on the colliding energy is investigated. We find that the EW correction suppresses the LO cross section significantly, and the ISR effect beyond O(α) is important near the threshold, but it is negligible in the high energy region. We provide the LO and EW corrected distributions of the transverse momenta and rapidities of final W − -boson and photon as well as the W -pair invariant mass. From the various kinematic distributions, we find that the EW correction strongly depends on the final state phase space. We investigate the leptonic decays of the final W-boson pair by adopting the narrow width approximation, and we find that the final produced photon and leptons can be well separated from each other.

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We report on the precision predictions for the e + e − → Z Zγ process including Z -boson leptonic decays at the ILC in the standard model (SM). The calculation includes the full next-to-leading (NLO) electroweak (EW) corrections and high order initial state radiation (h.o. ISR) contributions. We find that the NLO EW corrections heavily suppress the LO cross section, and the h.o. ISR effects are notable near the threshold while become small in high energy region. We present the LO and the NLO EW+h.o. ISR corrected distributions of the transverse momenta of final Z -boson and photon as well as the Z -pair invariant mass, and we investigate the corresponding NLO EW and h.o. ISR relative corrections. We also study the leptonic decays of the final Z -boson pair by adopting the MadSpin method where the spin correlation effect is involved. We conclude that both the h.o. ISR effects and the NLO EW corrections are important in exploring the Z Zγ production at the ILC.

Higgs boson production associated with a top quark pair is an important process in studying the nature of the newly discovered Higgs boson at the LHC. In this letter, we report on our calculations including the next-to-leading order (NLO) QCD and NLO electroweak corrections to the pp → tt H process in the standard model. We present the integrated cross sections at the 14 TeV LHC and even at the future proton-proton colliders with √ s = 33 and 100 TeV. Our calculation includes the top quark subsequent decays by adopting the narrow width approximation. The kinematic distributions of Higgs boson and top quark decay products at the LHC are provided. We find that the O(α 2 s α 2 ew ) corrections are quantitatively comparable with the O(α 3 s α ew ) corrections in some kinematic region.

The J/ψ + Z 0 associated production at the LHC is an important process in investigating the color-octet mechanism of non-relativistic QCD in describing the processes involving heavy quarkonium. We calculate the next-to-leading order (NLO) QCD corrections to the J/ψ + Z 0 associated production at the LHC within the factorization formalism of nonrelativistic QCD, and provide the theoretical predictions for the distribution of the J/ψ transverse momentum. Our results show that the differential cross section at the leading-order is significantly enhanced by the NLO QCD corrections. We conclude that the LHC has the potential to verify the color-octet mechanism by measuring the J/ψ + Z 0 production events.