Going to the light front with contour deformations

Abstract

We explore a new method to calculate the valence light-front wave function of a system of two interacting particles, which is based on contour deformations combined with analytic continuation methods to project the Bethe-Salpeter wave function onto the light front. In this proof-of-concept study, we solve the Bethe-Salpeter equation for a scalar model and find excellent agreement between the light-front wave functions obtained with contour deformations and those obtained with the Nakanishi method frequently employed in the literature. The contour-deformation method is also able to handle extensions of the scalar model that mimic certain features of QCD such as unequal masses and complex singularities. In principle the method is suitable for computing parton distributions on the light front such as PDFs, TMDs and GPDs in the future.

20 pages, 24 figures. Coincides with the version published in Phys. Rev. D

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Cited by in corpus (11)

• 50 Years of Quantum Chromodynamics
• Parton distributions of light quarks and antiquarks in the proton
• Pseudo-scalar mesons: light front wave functions, GPDs and PDFs
• Hadron and light nucleus radii from electron scattering
• An introductory lecture on Generalised Parton Distributions
• Dynamical mass generation in Minkowski space at QCD scale
• Four-quark scatterings in QCD II
• Parton distribution functions and transverse momentum dependence of heavy mesons
• The analytic structure of three-point functions from contour deformations
• Direct solution of Minkowski-space Bethe-Salpeter equation in the massive Wick-Cutkosky model
• Parton distribution and fragmentation functions with massive gluons