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arXiv · 2012.07546

Role of baryon resonances in the $π^-p \to ne^+e^-$ reaction within an effective-Lagrangian model

Miklós Zétényi·Deniz Nitt·Michael Buballa·Tetyana Galatyuk
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Abstract

We present a study of the reaction $π^-p \to ne^+e^-$ for $\sqrt{s}=1.49\,\textrm{GeV}$, including non-resonant Born terms and contributions of the $N(1440)$, $N(1520)$, $N(1535)$ resonances ($R$), using an effective-Lagrangian model, which we extended by a phenomenological phase factor at the $RNρ$ vertex function. We give predictions for both the differential cross section $dσ/dm$ and the spin density matrix elements of the virtual photon that decays into the lepton pair. In the studied energy range, the cross section is dominated by the Born and $N(1520)$ contributions.

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Miklós Zétényi, Deniz Nitt, Michael Buballa, Tetyana Galatyuk. 2021-01-08. Role of baryon resonances in the $π^-p \to ne^+e^-$ reaction within an effective-Lagrangian model. https://doi.org/10.1103/physrevc.104.015201

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