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Dilepton Production in Nucleon-Nucleon Reactions With and Without Hadronic Inelasticities

Kevin Haglin·Charles Gale
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Abstract

We calculate elementary proton-proton and neutron-proton bremsstrahlung and their contribution to the $e^+e^-$ invariant mass distribution. At 4.9 GeV, the proton-proton contribution is larger than neutron-proton, but it is small compared to recent data. We then make a first calculation of bremsstrahlung in nucleon-nucleon reactions with multi-hadron final states. Again at 4.9 GeV, the many-body bremsstrahlung is larger than simple nucleon-nucleon bremsstrahlung by more than an order of magnitude in the low-mass region. When the bremsstrahlung contributions are summed with Dalitz decay of the $η$, radiative decay of the $Δ$ and from two-pion annihilation, the result matches recent high statistics proton-proton data from the Dilepton Spectrometer collaboration.

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Kevin Haglin, Charles Gale. 1993-06-04. Dilepton Production in Nucleon-Nucleon Reactions With and Without Hadronic Inelasticities. https://doi.org/10.1103/physrevc.49.401

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