6533b854fe1ef96bd12adfd7
RESEARCH PRODUCT
Infrared singularities of scattering amplitudes in perturbative QCD
Matthias NeubertThomas Bechersubject
PhysicsQuarkQuantum chromodynamicsHigh Energy Physics - TheoryHigh Energy Physics::PhenomenologyGeneral Physics and AstronomyPerturbative QCDFOS: Physical sciencesJet (particle physics)Massless particleScattering amplitudeHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Soft-collinear effective theoryHigh Energy Physics - Theory (hep-th)Quantum mechanicsEffective field theoryHigh Energy Physics::ExperimentMathematical physicsdescription
An exact formula is derived for the infrared singularities of dimensionally regularized scattering amplitudes in massless QCD with an arbitrary number of legs, valid at any number of loops. It is based on the conjecture that the anomalous-dimension matrix of n-jet operators in soft-collinear effective theory contains only a single non-trivial color structure, whose coefficient is the cusp anomalous dimension of Wilson loops with light-like segments. Its color-diagonal part is characterized by two anomalous dimensions, which are extracted to three-loop order from known perturbative results for the quark and gluon form factors. This allows us to predict the three-loop coefficients of all 1/epsilon^k poles for an arbitrary n-parton scattering amplitudes, generalizing existing two-loop results.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-01-06 |