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Related papers: Four Loop Massless Propagators: an Algebraic Evalu…

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We present numerical results which are needed to evaluate all non-trivial master integrals for four-loop massless propagators, confirming the recent analytic results of[1]and evaluating an extra order in $\ep$ expansion for each master…

High Energy Physics - Phenomenology · Physics 2014-11-20 A. V. Smirnov , M. Tentyukov

Among the unitarity cuts of 4-loop massless propagators two kinds are currently fully known: the 2-particle cuts with 3 loops corresponding to form-factors, and the 5-particle phase-space integrals. In this paper we calculate master…

High Energy Physics - Phenomenology · Physics 2020-01-29 Vitaly Magerya , Andrey Pikelner

Among the unitarity cuts of massless 4-loop propagators two classes have remained unknown until recently: 2-loop 3-particle cuts, and 1-loop 4-particle cuts. In this article we shall discuss the calculation that completes the master…

High Energy Physics - Phenomenology · Physics 2019-12-16 Vitaly Magerya , Andrey Pikelner

We evaluate a Laurent expansion in dimensional regularization parameter $\epsilon=(4-d)/2$ of all the master integrals for four-loop massless propagators up to transcendentality weight twelve, using a recently developed method of one of the…

High Energy Physics - Theory · Physics 2015-05-30 R. N. Lee , A. V. Smirnov , V. A. Smirnov

We present the analytic calculation of all master integrals for 3-, 4-, and 5-particle semi-inclusive cuts of four-loop massless propagators by means of differential equations. We fix the integration constants by reducing the semi-inclusive…

High Energy Physics - Phenomenology · Physics 2025-03-26 Vitaly Magerya , Levente Fekésházy

We complete the calculation of master integrals for massless three-loop form factors by computing the previously-unknown three diagrams with nine propagators in dimensional regularisation. Each of the integrals yields a six-fold…

High Energy Physics - Phenomenology · Physics 2009-07-24 G. Heinrich , T. Huber , D. A. Kosower , V. A. Smirnov

We comment on the algorithm to compute periods using hyperlogarithms, applied to massless Feynman integrals in the parametric representation. Explicitly, we give results for all three-loop propagators with arbitrary insertions including…

High Energy Physics - Theory · Physics 2014-03-24 Erik Panzer

We develop a method to obtain $\epsilon$-expansions of massless two-point integrals in position space, based on the constraints implied by symmetries of the asymptotic expansion of conformal four-point integrals. Together with parametric…

High Energy Physics - Theory · Physics 2018-02-05 Alessandro Georgoudis , Vasco Gonçalves , Erik Panzer , Raul Pereira

We compute epsilon-expansions around 4 dimensions of a complete set of master integrals for momentum space five-loop massless propagator integrals in dimensional regularization, up to and including the first order with contributions of…

High Energy Physics - Phenomenology · Physics 2021-10-04 Alessandro Georgoudis , Vasco Gonçalves , Erik Panzer , Raul Pereira , Alexander V. Smirnov , Vladimir A. Smirnov

Extending an argument of [Baikov:2010hf] for the case of 5-loop massless propagators we prove a host of new exact model-independent relations between contributions proportional to odd and even zetas in generic \MSbar\ anomalous dimensions…

High Energy Physics - Phenomenology · Physics 2018-08-01 P. A. Baikov , K. G. Chetyrkin

We use dimensional recurrence relations and analyticity to calculate four-loop propagator-type master integrals in the heavy-quark effective theory. Compared to previous applications of the DRA method, we apply a new technique of fixing…

High Energy Physics - Phenomenology · Physics 2023-03-01 Roman N. Lee , Andrey F. Pikelner

We present analytical results for all master integrals for massless three-point functions, with one off-shell leg, at four loops. Our solutions were obtained using differential equations and direct integration techniques. We review the…

Several powerful techniques for evaluating massless scalar Feynman diagrams are developed, viz: the solution of recurrence relations to evaluate diagrams with arbitrary numbers of loops in $n=4-2\omega$ dimensions; the discovery and use of…

High Energy Physics - Theory · Physics 2016-04-28 David J. Broadhurst

We evaluate three typical four-loop non-planar massless propagator diagrams in a Taylor expansion in dimensional regularization parameter $\epsilon=(4-d)/2$ up to transcendentality weight twelve, using a recently developed method of one of…

High Energy Physics - Theory · Physics 2011-08-17 R. N. Lee , A. V. Smirnov , V. A. Smirnov

I obtain identities satisfied by the 3-loop self-energy master integrals with four or five propagators with generic masses, including the derivatives with respect to each of the squared masses and the external momentum invariant. These…

High Energy Physics - Phenomenology · Physics 2023-03-29 Stephen P. Martin

We provide analytic results for two-loop four-point master integrals with one massive propagator and one massive leg relevant to single top production. Canonical bases of master integrals are constructed and the Simplified Differential…

High Energy Physics - Phenomenology · Physics 2023-05-31 Nikolaos Syrrakos

We study multi-propagator angular integrals, a class of phase-space integrals relevant to processes with multiple observed final states and a test-bed for transferring loop-integral technology to phase space integrals without reversed…

High Energy Physics - Phenomenology · Physics 2025-10-17 Juliane Haug , Vladimir A. Smirnov , Fabian Wunder

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…

High Energy Physics - Phenomenology · Physics 2016-08-30 Andreas von Manteuffel , Erik Panzer , Robert M. Schabinger

The class of the two-loop massless crossed boxes, with light-like external legs, is the final unresolved issue in the program of computing the scattering amplitudes of 2 --> 2 massless particles at next-to-next-to-leading order. In this…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. Anastasiou , T. Gehrmann , C. Oleari , E. Remiddi , J. B. Tausk

We consider the maximal cut of a three-loop four point function with massless kinematics. By applying Groebner bases and primary decomposition we develop a method which extracts all ten propagator master integral coefficients for an…

High Energy Physics - Phenomenology · Physics 2015-06-05 Simon Badger , Hjalte Frellesvig , Yang Zhang
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