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arXiv · 0903.4297

New constraints on the Pion EM form factor using Pi'(-Q^2)

Gauhar Abbas·B. Ananthanarayan·S. Ramanan
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Abstract

We study the constraints arising on the expansion parameters c and d of the Pion electromagnetic form factor from the inclusion of pure space-like data and the phase of time-like data along with one space-like datum, using as input the first derivative of the QCD polarization amplitude Pi'(-Q^2). These constraints when combined with other analyses, provide a valuable check on a determination of c due to Guo et al. and on our previous work where pionic contribution to the (g-2) of the muon was used as the input. This work further illustrates the power of analyticity techniques in form factor analysis.

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Gauhar Abbas, B. Ananthanarayan, S. Ramanan. 2009-04-15. New constraints on the Pion EM form factor using Pi'(-Q^2). https://doi.org/10.1140/epja/i2009-10802-x

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