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General analysis of polarization phenomena in $ e^++e^-\to N+\bar N$ for axial parametrization of two--photon exchange

G. I. Gakh·E. Tomasi-Gustafsson
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Abstract

General properties of the differential cross section and of the polarization observables are derived for the $e^++e^-\to N+\bar N$ reaction, in presence of two--photon exchange. Polarization effects are investigated for longitudinally polarized electron and polarized antinucleon and/or polarized nucleon in the final state. The single--spin asymmetry induced by the transverse polarization of the electron beam is also discussed.

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G. I. Gakh, E. Tomasi-Gustafsson. 2005-11-20. General analysis of polarization phenomena in $ e^++e^-\to N+\bar N$ for axial parametrization of two--photon exchange. https://doi.org/10.1016/j.nuclphysa.2006.03.009

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