2017/11/30 by Rikkert Frederix, Davide Pagani, Marco Zaro · 5 citations
Physics and Astronomy · #Electroweak interaction #Factorization #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Physics beyond the Standard Model #Production (economics) #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Scattering #hep-ph
paper · pdf · doi:10.1007/jhep02(2018)031
40 pages, 8 figures; v2: published version with minor changes w.r.t original submission
openalex created_date 2017/11/17 · openalex publication_date 2018/02/01 · arxiv created 2018/02/09 · arxiv updated 2018/04/04 · openalex updated_date 2026/08/06
We calculate the complete-NLO predictions for ttW± and tttt production in proton-proton collisions at 13 and 100 TeV. All the non-vanishing contributions of O(αsiαj) with i + j = 3, 4 for ttW± and i + j = 4, 5 for tttt are evaluated without any approximation. For ttW± we find that, due to the presence of tW → tW scattering, at 13(100) TeV the O(αsα3) contribution is about 12(70)% of the LO, i.e., it is larger than the so-called NLO EW corrections (the O(αs2α2) terms) and has opposite sign. In the case of tttt production, large contributions from electroweak tt → tt scattering are already present at LO in the O(αs3α ) and O(αs2α2) terms. For the same reason we find that both NLO terms of O(αs4α ) , i.e., the NLO EW corrections, and O(αs3α2) are large (±15% of the LO) and their relative contributions strongly depend on the values of the renormalisation and factorisation scales. However, large accidental cancellations are present (away from the threshold region) between these two contributions. Moreover, the NLO corrections strongly depend on the kinematics and are particularly large at the threshold, where even the relative contribution from O(αs2α3) terms amounts to tens of percents.