1994/03/31 by A. Brandenburg, S. J. Brodsky, Stanley J. Brodsky +4 · 5 citations
Physics and Astronomy · #Amplitude #Bound state #Distribution (mathematics) #Drell–Yan process #Electron #Geometry #High-Energy Particle Collisions Research #Lepton #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Parton #Perturbative QCD #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Twist #hep-ph
paper · pdf · doi:10.1103/physrevlett.73.939
published as Phys.Rev.Lett.73:939-942,1994 · Plain Tex, 9 pages, 3 appended figures, SLAC-PUB-6464-revised
arxiv created 1994/06/04 · openalex publication_date 1994/08/15 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We calculate the angular distribution of the lepton produced in the Drell-Yan reaction taking into account pion bound state effects. This is particularly interesting since the standard perturbative QCD prediction is inconsistent with the data. We work in the kinematic region where one of the pion constituents goes far off shell, which allows us to treat the bound state problem perturbatively. We show that the angular distribution is very sensitive to the shape of the pion distribution amplitude. The model we discuss fits the data if we choose a two-humped pion distribution amplitude suggested by QCD sum rules.