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DOE OSTI · 2006663

Top tree amplitudes for higher order calculations

Campbell, John M.·Ellis, R. Keith
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Abstract

We present compact analytic results for tree-level amplitudes containing a $t\bar{t}$ pair accompanied by up to four massless partons $t\bar{t}gg$, $t\bar{t}ggg$, $t\bar{t}gggg$, $t\bar{t}q\bar{q}$, $t\bar{t}q\bar{q}g$, $t\bar{t}q\bar{q}gg$, and $t\bar{t}q\bar{q}q'\bar{q'}$. The results, obtained using BCFW on-shell recursion, are based both on previous published results and on the new calculations performed in this paper. These amplitudes are sufficient to calculate the production of a $t\bar{t}$ pair and zero, one, or two light parton jets, with the option to include the tree-level decays t → bνe + and $\bar{t} → \bar{b}e^-\bar{v}$ efficiently. Our results are part of the NNLO corrections to $t\bar{t}$ production including the decay correlations for on-shell top quarks.

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSHigher-order perturbative calculationsScattering amplitudesTop quark

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Campbell, John M., Ellis, R. Keith. 2023-10-20. Top tree amplitudes for higher order calculations. https://doi.org/10.1007/jhep10(2023)125

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