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arXiv · 1308.1062

Recursion relations and scattering amplitudes in the light-front formalism

Christian A. Cruz-Santiago·Anna M. Stasto
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Abstract

The fragmentation functions and scattering amplitudes are investigated in the framework of light-front perturbation theory. It is demonstrated that, the factorization property of the fragmentation functions implies the recursion relations for the off-shell scattering amplitudes which are light-front analogs of the Berends-Giele relations. These recursion relations on the light-front can be solved exactly by induction and it is shown that the expressions for the off-shell light-front amplitudes are represented as a linear combinations of the on-shell amplitudes. By putting external particles on-shell we recover the scattering amplitudes previously derived in the literature.

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Christian A. Cruz-Santiago, Anna M. Stasto. 2013-08-05. Recursion relations and scattering amplitudes in the light-front formalism. https://doi.org/10.1016/j.nuclphysb.2013.07.019

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