NNLO QCD predictions for ttW production with two-loop amplitudes evaluated explicitly in the generalised leading-colour limit.
On-the-fly reduction of open loops
4 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
Building on the open-loop algorithm we introduce a new method for the automated construction of one-loop amplitudes and their reduction to scalar integrals. The key idea is that the factorisation of one-loop integrands in a product of loop segments makes it possible to perform various operations on-the-fly while constructing the integrand. Reducing the integrand on-the-fly, after each segment multiplication, the construction of loop diagrams and their reduction are unified in a single numerical recursion. In this way we entirely avoid objects with high tensor rank, thereby reducing the complexity of the calculations in a drastic way. Thanks to the on-the-fly approach, which is applied also to helicity summation and for the merging of different diagrams, the speed of the original open-loop algorithm can be further augmented in a very significant way. Moreover, addressing spurious singularities of the employed reduction identities by means of simple expansions in rank-two Gram determinants, we achieve a remarkably high level of numerical stability. These features of the new algorithm, which will be made publicly available in a forthcoming release of the OpenLoops program, are particularly attractive for NLO multi-leg and NNLO real-virtual calculations.
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hep-ph 4representative citing papers
NNLO QCD predictions for ttW production at hadron colliders using direct two-loop amplitude computation in the generalised leading-colour limit.
NNLO+PS matching for gluon-fusion Higgs pair production is implemented in MiNNLOPS with approximate top-mass effects, validated against fixed-order NNLO and compared to GENEVA, with results for decay channels and trilinear coupling variations.
Disperon QED is a new technique that feeds experimental data into higher-order QED loop calculations in Monte Carlo generators via dispersion relations and threshold subtraction.
citing papers explorer
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NNLO QCD predictions for $t\bar{t}W$ production at the LHC
NNLO QCD predictions for ttW production with two-loop amplitudes evaluated explicitly in the generalised leading-colour limit.
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NNLO QCD predictions for $t\bar t W$ production at hadron colliders
NNLO QCD predictions for ttW production at hadron colliders using direct two-loop amplitude computation in the generalised leading-colour limit.
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NNLO+PS Higgs-pair production in MiNNLOPS
NNLO+PS matching for gluon-fusion Higgs pair production is implemented in MiNNLOPS with approximate top-mass effects, validated against fixed-order NNLO and compared to GENEVA, with results for decay channels and trilinear coupling variations.
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Disperon QED
Disperon QED is a new technique that feeds experimental data into higher-order QED loop calculations in Monte Carlo generators via dispersion relations and threshold subtraction.