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arXiv · 1206.2549

γ*γ\rightarrow π^0 transition form factor at low-energies from a model-independent approach

P. Masjuan
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Abstract

The recent measured γ*γ\rightarrow π^0 transition form factor in the space-like region by the Belle Collaboration together with the previous published results by CLEO, CELLO and BABAR collaborations are analyzed using the mathematical theory of Padé Approximants which provides a good and systematic description of the low energy region exemplified here with the extraction of the slope a_π and curvature b_π of the form factor in a model-independent way. The impact of them on the pion exchange contribution to the hadronic light-by-light scattering part of the anomalous magnetic moment a_μ is also discussed.

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P. Masjuan. 2012-11-19. γ*γ\rightarrow π^0 transition form factor at low-energies from a model-independent approach. https://doi.org/10.1103/physrevd.86.094021

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