Pion-photon transition form factor. Living on the QCD frontier
Abstract
An analysis of all available data (CELLO, CLEO, \babar) in the range GeV for the pion-photon transition form factor in terms of light-cone sum rules with next-to-leading-order accuracy is discussed, including twist-four contributions and next-to-next-to-leading order and twist-six corrections---the latter two via uncertainties. The antithetic trend between the \babar data for the and those for the transition is pointed out, emphasizing the underlying antagonistic mechanisms: endpoint enhancement for the first and endpoint-suppression for the second---each associated with pseudoscalar meson distribution amplitudes with distinct endpoint characteristics.
Cite
@article{arxiv.1109.2718,
title = {Pion-photon transition form factor. Living on the QCD frontier},
author = {N. G. Stefanis},
journal= {arXiv preprint arXiv:1109.2718},
year = {2012}
}
Comments
6 pages, 3 figures; needs style files svglov2.clo, svjour2.cls (supplied). Presented at LIGHTCONE 2011, 23 - 27 May, 2011, Dallas, USA. Accepted for publication in Few-Body Systems. In v2 name of second author in [28] corrected. V3 is final version, published online 23. Sep 2011