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$ρ$-Meson Production and Decay in Proton-Nucleus Collisions

A. Sibirtsev·W. Cassing
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Abstract

We analyze the production of $ρ$-mesons in $p + A$ reactions including both the production by proton-nucleon as well as pion-nucleon collisions within a coupled channel transport approach. The final state interactions of the $ρ$-meson with nucleons are evaluated from a resonance model which allows to extract elastic and inelastic cross sections. We include the latter final state interactions, the $ρ$-meson decay into two pions as well as the final pion-nucleon interactions within the transport approach. We find the invariant mass distribution of pion pairs to be sensitive to the $ρ$-meson properties in the nuclear medium. However, due to the strong final state interactions of pions only light targets like $^{12}C$ might be suited to extract a $ρ$-signal from the uncorrelated two pion background which carries information about the in-medium properties of the $ρ$-meson.

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A. Sibirtsev, W. Cassing. 1997-12-02. $ρ$-Meson Production and Decay in Proton-Nucleus Collisions. https://doi.org/10.1016/s0375-9474(97)00647-7

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