Full one-loop amplitudes from tree amplitudes

Abstract

We establish an efficient polynomial-complexity algorithm for one-loop calculations, based on generalized $D$-dimensional unitarity. It allows automated computations of both cut-constructible {\it and} rational parts of one-loop scattering amplitudes from on-shell tree amplitudes. We illustrate the method by (re)-computing all four-, five- and six-gluon scattering amplitudes in QCD at one-loop.

27 pages, revtex

References in corpus (8)

• Reducing full one-loop amplitudes to scalar integrals at the integrand level
• Direct extraction of one-loop integral coefficients
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Cited by in corpus (26)

• An Automated Implementation of On-Shell Methods for One-Loop Amplitudes
• On the Rational Terms of the one-loop amplitudes
• NLO QCD corrections to pp -> t anti-t b anti-b + X at the LHC
• Automation of the Dipole Subtraction Method in MadGraph/MadEvent
• Direct Extraction Of One Loop Rational Terms
• NLO QCD corrections to tri-boson production
• On the Numerical Evaluation of One-Loop Amplitudes: the Gluonic Case
• Optimizing the Reduction of One-Loop Amplitudes
• Double-Cut of Scattering Amplitudes and Stokes' Theorem
• Closed-Form Decomposition of One-Loop Massive Amplitudes
• One-loop amplitudes for W+3 jet production in hadron collisions
• Multi-gluon one-loop amplitudes using tensor integrals
• The one-loop gluon amplitude for heavy-quark production at NNLO
• One-loop phi-MHV amplitudes using the unitarity bootstrap: the general helicity case
• Polynomial Structures in One-Loop Amplitudes
• One-Loop Gluonic Amplitudes from Single Unitarity Cuts
• Multi-gluon one-loop amplitudes numerically
• One-Loop Calculations with BlackHat
• Unitarity Method with Spurious Pole
• Generalised Unitarity At One-Loop With Massive Fermions
• A Fully Numerical Approach to One-Loop Amplitudes
• Calculating gluon one-loop amplitudes numerically
• Recent theoretical progress in perturbative QCD
• MHV Lagrangians for Yang--Mills and QCD
• On the Cuts of Scattering Amplitudes
• Constructing QCD one-loop amplitudes