Pion transition form factor in the Regge approach and incomplete vector-meson dominance

Details Pion transition form factor in the Regge approach and incomplete vector-meson dominance Pion transition form factor in the Regge approach and incomplete vector-meson dominance

2010-04-06

arxiv.org/abs/1004.0837v1

Physics

High Energy Physics

High Energy Physics - Phenomenology

11 pages, 7 figures

Scientific paper

The concept of incomplete vector-meson dominance and Regge models is applied to the transition form factor of the pion. First, we argue that variants of the chiral quark model fulfilling the chiral anomaly may violate the Terazawa-West unitarity bounds, as these bounds are based on unverified assumptions for the real parts of the amplitudes, precluding a possible presence of polynomial terms. A direct consequence is that the transition form factor need not necessarily vanish at large values of the photon virtuality. Moreover, in the range of the BaBar experiment, the Terazawa-West bound is an order of magnitude above the data, thus is of formal rather than practical interest. Then we demonstrate how the experimental data may be properly explained with incomplete vector-meson dominance in a simple model with one state, as well as in more sophisticated Regge models. Generalizations of the simple Regge model along the lines of Dominguez result in a proper description of the data, where one may adjust the parameters in such a way that the Terazawa-West bound is satisfied or violated. We also impose the experimental constraint from the Z -> pi0 gamma decay. Finally, we point out that the photon momentum asymmetry parameter may noticeably influence the precision analysis.

Affiliated with

Also associated with

No associations

Rating

Pion transition form factor in the Regge approach and incomplete vector-meson dominance does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Pion transition form factor in the Regge approach and incomplete vector-meson dominance, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pion transition form factor in the Regge approach and incomplete vector-meson dominance will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-57338