paper

The Evolution of the Pion Distribution Amplitude in Next-to-Leading Order

arXiv:hep-ph/9411338 · doi:10.1103/PhysRevD.51.3855

Abstract

The evolution of the pion distribution amplitude in next-to-leading order is studied for a fixed and a running coupling constant. In both cases, the evolution provides a logarithmic modification in the endpoint region. Assuming a simple parameterization of the distribution amplitude at a scale of , it is shown numerically that these effects are large enough at that they have to be taken into account in the next-to-leading-order analysis for exclusive processes. Alternatively, by introducing a new distribution amplitude that evolves more smoothly, this logarithmic modification can be included in the hard-scattering part of the considered process.

17 pages LaTeX + 3 uuencoded and compressed postscript figures

References in corpus (2)

Cited by in corpus (73)