0000000000293311

AUTHOR

Erik Panzer

0000-0002-9897-5812

showing 2 related works from this author

A quasi-finite basis for multi-loop Feynman integrals

2014

We present a new method for the decomposition of multi-loop Euclidean Feynman integrals into quasi-finite Feynman integrals. These are defined in shifted dimensions with higher powers of the propagators, make explicit both infrared and ultraviolet divergences, and allow for an immediate and trivial expansion in the parameter of dimensional regularization. Our approach avoids the introduction of spurious structures and thereby leaves integrals particularly accessible to direct analytical integration techniques. Alternatively, the resulting convergent Feynman parameter integrals may be evaluated numerically. Our approach is guided by previous work by the second author but overcomes practical …

High Energy Physics - TheoryQuantum chromodynamicsPhysicsNuclear and High Energy PhysicsBasis (linear algebra)FOS: Physical sciencesPropagatorHigh Energy Physics - Phenomenologysymbols.namesakeDimensional regularizationHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - Theory (hep-th)Euclidean geometrysymbolsApplied mathematicsFeynman diagramIntegration by partsReduction (mathematics)Journal of High Energy Physics
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Computation of form factors in massless QCD with finite master integrals

2016

We present the bare one-, two-, and three-loop form factors in massless Quantum Chromodynamics as linear combinations of finite master integrals. Using symbolic integration, we compute their $\epsilon$ expansions and thereby reproduce all known results with an independent method. Remarkably, in our finite basis, only integrals with a less-than-maximal number of propagators contribute to the cusp anomalous dimensions. We report on indications of this phenomenon at four loops, including the result for a finite, irreducible, twelve-propagator form factor integral. Together with this article, we provide our automated software setup for the computation of finite master integrals.

High Energy Physics - TheoryQuantum chromodynamicsPhysicsBasis (linear algebra)010308 nuclear & particles physicsComputationForm factor (quantum field theory)PropagatorFOS: Physical sciences01 natural sciencesMassless particleHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - Theory (hep-th)0103 physical sciences010306 general physicsLinear combinationSymbolic integrationMathematical physics
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