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Di-electrons from $η$ meson Dalitz decay in proton-proton collisions

L. P. Kaptari·B. Kampfer
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Abstract

The reaction $ pp \to pp η\to pp γe^+ e^-$ is discussed within a covariant effective meson-nucleon theory. The model is adjusted to data of the subreaction $pp \to pp η$. Our focus is on di-electrons from Dalitz decays of $η$ mesons, $η\to γγ^* \toγe^+e^-$, and the role of the corresponding transition form factor $F_{ηγγ^*}$. Numerical results are presented for the intermediate energy kinematics of HADES experiments.

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L. P. Kaptari, B. Kampfer. 2007-02-09. Di-electrons from $η$ meson Dalitz decay in proton-proton collisions. https://doi.org/10.1140/epja%2Fi2007-10453-y

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