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e+e- pair production from nucleon targets in the resonance region

Madeleine Soyeur·Matthias F. M. Lutz
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Abstract

We present consistent theoretical descriptions of the $πN \to e^+e^- N$ and $γN \to e^+e^- N$ reactions on proton and neutron targets for total center of mass energies $\sqrt s$ ranging between 1.50 GeV and 1.75 GeV. These reactions are complementary to study the coupling of low-lying baryon resonances to vector meson-nucleon channels. We show in particular how the resonant structure of the amplitudes for both processes generates specific and large quantum interferences between $ρ$- and $ω$-meson decays into $e^+e^-$ pairs. Data on the $πN \to e^+e^- N$ and $γN \to e^+e^- N$ reactions are expected in the near future from the HADES program at GSI and from dilepton studies with CLAS at JLab.

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Madeleine Soyeur, Matthias F. M. Lutz. 2004-02-26. e+e- pair production from nucleon targets in the resonance region. https://arxiv.org/abs/nucl-th/0402095

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