We present the complete two-loop QCD amplitudes for the production of a top-quark pair in the quark--antiquark annihilation and gluon-fusion channels in analytic form up to order $\mathcal{O}(\varepsilon^2)$. Our analysis maintains full dependence on the top-quark mass and on the number of colours. The amplitudes are expressed in terms of 417 master integrals, which we compute by means of differential equations in $\varepsilon$-factorised form. Their calculation involves several elliptic curves and a hyperelliptic curve of genus two, which makes top-quark pair production an ideal arena for recent methods to construct canonical bases beyond polylogarithms. To the best of our knowledge, this is the first scattering amplitude in which iterated integrals related to a genus-two surface survive in the finite remainder in four space-time dimensions. We provide high-precision series expansions at the threshold and combine them with the numerical solution of the differential equations in a code that evaluates the UV-renormalised infrared-finite remainders at arbitrary points of the physical phase space.
We complete the calculation of the two-loop Feynman integrals required for the next-to-next-to-leading order QCD corrections to on-shell top--antitop production in association with a photon at hadron colliders, in the leading-colour approximation. The same integrals also enter the subleading-colour corrections to top--...
Souvik Bera, C. Brancaccio, D. Canko et al.· 0 citations
We present a complete analytic calculation of the next-to-leading-order (NLO) QCD cross sections for the production of an electroweak vector boson ($W^\pm$, $Z/\gamma^*$) at finite transverse momentum, decomposed into the full set of helicity cross sections that determine the angular coefficients $A_0$-$A_7$ of the lep...
S. Camarda, L. Cieri, Giancarlo Ferrera et al.· 1 citation
We investigate the interference of a heavy radion with the QCD continuum in top-quark-pair production at the High-Luminosity Large Hadron Collider, restricting the numerical study to the pure-radion limit $\xi=0$. The gluon-fusion amplitude combines the QCD trace anomaly with the exact finite-top-mass loop form factor,...
We study the sensitivity of top-quark pair production at the FCC-ee to heavy new physics, parametrised in the Standard Model effective field theory, using discriminants based on matrix elements. The analysis includes detector reconstruction effects, obtained with a fast simulation of the IDEA detector concept, and jet...
Jacopo De Piccoli, G. Durieux, S. S. Cruz et al.· 0 citations
We determine the universal singular structure of rapidity distributions for color-singlet production in hadron collisions through next-to-next-to-next-to-leading order (N3LO) in QCD. Our result captures the full singular contributions as either partonic momentum fraction approaches one, including the delta-function ter...
Federica Devoto, B. Mistlberger, Gherardo Vita· 0 citations
We present the first direct computation of the two-loop QCD virtual corrections to the production of a top-antitop quark pair in association with a Higgs boson ($t\bar{t}H$) at the LHC. We focus on the quark-antiquark channel and perform the calculation in the generalised leading-colour approximation. We combine state-...
Xiang Chen, M. Grazzini, S. Kallweit· 1 citation
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