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Measuring the Phases of G_E and G_M of the Nucleon

Stephen Rock
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Abstract

The nucleon electromagnetic form factors G_E and G_M are complex quantities in the time-like region. The absolute values can be determined by measuring the angular distribution of the nucleons in e^+ e^- --> N N-bar. The complex phase can only be determined by measuring one or more polarizations of the initial or final state. For PEP-N, we can use unpolarized e+ and e- and measure the polarization of one of the outgoing nucleons.

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Stephen Rock. 2001-06-22. Measuring the Phases of G_E and G_M of the Nucleon. https://arxiv.org/abs/hep-ex/0106084

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