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arXiv · 0803.0696

Can one measure C-odd asymmetry in e+e- --> pi+pi-

J. Layssac·S. Narison
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Abstract

C-odd asymmetry can be studied from an accurate measurement of the angular distribution due to the interference between the S- and P-waves in e+e- --> pi+ pi- at order alpha^3. The asymmetry is dominated by the pion rescattering diagram which is enhanced by the presence of the ln(s/m^2_e), and is quite large (10% at theta=30^0 and sqrt{s} < M_{f_2}) compared to alpha/pi=0.3%. This process can also be used for alternatively measuring the size of the rescattering term and the phase of the S-wave amplitude, but does not help to solve the present discrepancy between the hadronic spectral functions from e+e- and tau-decay data.

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J. Layssac, S. Narison. 2008-11-30. Can one measure C-odd asymmetry in e+e- --> pi+pi-. https://doi.org/10.1016/j.nuclphysbps.2008.12.047

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