Top quark pair production and decay at hadron colliders

Abstract

In ongoing and upcoming hadron collider experiments, top quark physics will play an important rôle in testing the Standard Model and its possible extensions. In this work we present analytic results for the differential cross sections of top quark pair production in hadronic collisions at next-to-leading order in the QCD coupling, keeping the full dependence on the spins of the top quarks. These results are combined with the corresponding next-to-leading order results for the decay of polarized top quarks into dilepton, lepton plus jets, and all jets final states. As an application we predict double differential angular distributions which are due to the QCD-induced top quark spin correlations in the intermediate state. In addition to the analytic results, we give numerical results in terms of fit functions that can easily be used in an experimental analysis.

Off-shell vs on-shell modelling of top quarks in photon associated production

“…It allows to make predictions for realistic final states described in terms of light and b-jets, charged leptons as well as missing transverse momentum, thus, allowing direct comparisons with cross section measurements in the fiducial phase space regions. Prominent examples include the calculations for the pp → tt(j) process at NLO QCD and theoretical predictions for tt at NNLO in QCD [35][36][37][38][39]. The NWA is well established and allows factorisation of the cross section into production times decays due to the following relation 1…”

An NLO+PS generator for $${\varvec{t \bar{t}}}$$ t t ¯ and $${\varvec{W t}}$$ W t production and decay including non-resonant and interference effects

“…[31]. The best available NWA fixed-order calculations implement NLO QCD corrections to the production and decay parts with exact spin correlations [32][33][34]. The ttb NLO dec 2 generator of Ref.…”

NLO electroweak corrections to off-shell top-antitop production with leptonic decays at the LHC

“…Therefore its production and decay rate should be computed and measured with the highest possible precision. In that respect, not only next-to-leading-order (NLO) QCD corrections [7][8][9][10][11][12][13][14][15][16][17][18] including parton-shower matching [19][20][21][22][23][24] but also next-to-next-to-leadingorder (NNLO) QCD [25][26][27], resummation [28][29][30][31][32], and NLO electroweak (EW) corrections [33][34][35][36][37][38][39][40][41][42][43] must be considered. The latter have so far exclusively been computed for on-shell top quarks.…”