The Evolution of the Pion Distribution Amplitude in Next-to-Leading Order
High Energy Physics - Phenomenology
2016-09-01 v1
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.
Keywords
Cite
@article{arxiv.hep-ph/9411338,
title = {The Evolution of the Pion Distribution Amplitude in Next-to-Leading Order},
author = {Dieter Müller},
journal= {arXiv preprint arXiv:hep-ph/9411338},
year = {2016}
}
Comments
17 pages LaTeX + 3 uuencoded and compressed postscript figures