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Related papers: On-shell recursion for massive fermion currents

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We extend the argument presented by Benincasa, Boucher-Veronneau, and Cachazo to show that graviton tree amplitudes are well behaved under large complex deformations of the momenta of a pair of like-helicity gravitons. This shows that BCFW…

High Energy Physics - Theory · Physics 2008-11-26 Anthony Hall

We construct two and three-line shifts for tree-level amplitude with massless and/or massive particles, and provide a method to construct general multi-line shifts for all masses. We choose the massless-massive BCFW shift from these shifts…

High Energy Physics - Theory · Physics 2022-07-06 Chao Wu , Shou-Hua Zhu

We study in detail the general structure and further properties of the tree-level amplitudes in the SU(N) nonlinear sigma model. We construct the flavor-ordered Feynman rules for various parameterizations of the SU(N) fields U(x), write…

High Energy Physics - Theory · Physics 2015-06-15 Karol Kampf , Jiri Novotny , Jaroslav Trnka

Modern on-shell S-matrix methods may dramatically improve our understanding of perturbative quantum gravity, but current foundations of on-shell techniques for General Relativity still rely on off-shell Feynman diagram analysis. Here, we…

High Energy Physics - Theory · Physics 2015-05-20 David A. McGady , Laurentiu Rodina

We present a proof of the Britto-Cachazo-Feng-Witten tree-level recursion relation for gluon amplitudes in QCD, based on a direct equivalence between BCFW decompositions and Feynman diagrams. We demonstrate that this equivalence can be made…

High Energy Physics - Phenomenology · Physics 2009-01-07 Petros D. Draggiotis , Ronald H. P. Kleiss , Achilleas Lazopoulos , Costas G. Papadopoulos

We use the pinch technique formalism to construct the gauge-independent off-shell two-loop fermion self-energy, both for Abelian (QED) and non-Abelian (QCD) gauge theories. The new key observation is that all contributions originating from…

High Energy Physics - Phenomenology · Physics 2009-11-07 Daniele Binosi , Joannis Papavassiliou

We present examples of on-shell recurrence relations for determining rational functions appearing in one-loop QCD amplitudes. In particular, we give relations for one-loop QCD amplitudes with all legs of positive helicity, or with one leg…

High Energy Physics - Theory · Physics 2010-11-15 Zvi Bern , Lance J. Dixon , David A. Kosower

We construct tree-level amplitude for massive particles using on-shell recursion relations based on two classes of momentum shifts: an all-line transverse shift that deforms momentum by its transverse polarization vector, and a massive…

High Energy Physics - Phenomenology · Physics 2024-11-14 Yohei Ema , Ting Gao , Wenqi Ke , Zhen Liu , Kun-Feng Lyu , Ishmam Mahbub

We calculate gauge theory one-loop amplitudes with the aid of the complex shift used in the Britto-Cachazo-Feng-Witten (BCFW) recursion relations of tree amplitudes. We apply the shift to the integrand and show that the contribution from…

High Energy Physics - Theory · Physics 2013-05-30 Savan Kharel , George Siopsis

We use the recently developed massive spinor-helicity formalism [1] of Arkani- Hamed et al. to propose a new class of recursion relations for tree-level amplitudes in gauge theories. These relations are based on a combined complex…

High Energy Physics - Theory · Physics 2021-05-13 Sourav Ballav , Arkajyoti Manna

We study the compatibility of recursive techniques with the classical limit of scattering amplitudes through the construction of the classical Compton amplitude for general spinning compact objects. This is done using BCFW recursion on…

High Energy Physics - Theory · Physics 2023-06-07 Kays Haddad

We explore the on-shell recursion for tree-level scattering amplitudes with massive spinning particles. Based on the factorization structure encoded in the same way by two different recursion relations, we conjecture an all-multiplicity…

High Energy Physics - Theory · Physics 2022-03-03 Achilleas Lazopoulos , Alexander Ochirov , Canxin Shi

We analyze the off-shell scattering amplitudes in the framework of the light-front perturbation theory. It is shown that the previously derived recursion relation between tree level off-shell amplitudes in this formalism actually resums…

High Energy Physics - Phenomenology · Physics 2015-06-24 C. Cruz-Santiago , P. Kotko , A. Stasto

We provide a new set of on-shell recursion relations for tree-level scattering amplitudes, which are valid for any non-trivial theory of massless particles. In particular, we reconstruct the scattering amplitudes from (a subset of) their…

High Energy Physics - Theory · Physics 2015-05-28 Paolo Benincasa , Eduardo Conde

The standard Feynman rules used for perturbative calculations in quantum chromodynamics (QCD) are derived from a Lagrangian that is first-order in derivatives. It includes a three-point quark-gluon vertex which obscures the precise…

High Energy Physics - Phenomenology · Physics 2025-03-04 Victor Miguel Banda Guzmán , Adnan Bashir

In this paper we consider tree-level gauge invariant off-shell amplitudes (Wilson line form factors) in $\mathcal{N}=4$ SYM. For the off-shell amplitudes with one leg off-shell we present a conjecture for their Grassmannian integral…

High Energy Physics - Theory · Physics 2017-04-26 L. V. Bork , A. I. Onishchenko

In the Color Glass Condensate framework, the colliding projectiles are described as classical color currents. Gluon production at leading order in the coupling is obtained from the retarded solution of the classical Yang-Mills equations,…

Nuclear Theory · Physics 2026-05-05 Francois Gelis

Using newly proposed BCF/BCFW recursion relations, compact formulas are obtained for tree-level n-gluon amplitudes of helicity structure --++...+. We then make an extension of these recursion relations to include fermions of multi-flavors,…

High Energy Physics - Theory · Physics 2008-11-26 Mingxing Luo , Congkao Wen

In this article a first step is made towards the extension of Britto-Cachazo-Feng-Witten (BCFW) tree level on-shell recursion relations to integrands and integrals of scattering amplitudes to arbitrary loop order. Surprisingly, it is shown…

High Energy Physics - Theory · Physics 2010-11-30 Rutger H. Boels

In this article, we analyze the boundary behaviors of pure Yang-Mills amplitudes under adjacent and non adjacent BCFW shifts in Feynman gauge. We introduce reduced vertexes for Yang-Mills fields, prove that these reduced vertexes are…

High Energy Physics - Theory · Physics 2013-08-09 Yun Zhang , Gang Chen