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e^+e^- Pair Production from $γ$ A Reactions

M. Effenberger·E. L. Bratkovskaya·U. Mosel
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Abstract

We present a calculation of e^+e^- production in $γA$ reactions at MAMI and TJNAF energies within a semi-classical BUU transport model. Dilepton invariant mass spectra for $γ$C, $γ$Ca and $γ$Pb are calculated at 0.8, 1.5 and 2.2 GeV. We focus on observable effects of medium modifications of the $ρ$ and $ω$ mesons. The in-medium widths of these mesons are taken into account in a dynamical, consistent way. We discuss the transport theoretical treatment of broad resonances.

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M. Effenberger, E. L. Bratkovskaya, U. Mosel. 1999-08-27. e^+e^- Pair Production from $γ$ A Reactions. https://doi.org/10.1103/physrevc.60.044614

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