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The $ρ$ Spectral Function in a Relativistic Resonance Model

M. Post·S. Leupold·U. Mosel
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Abstract

We calculate the spectral function $A_ρ$ of the $ρ$ meson in nuclear matter. The calculation is performed in the {\it low density} approximation, where the in-medium self energy $Σ_{med}$ is completely determined by the vacuum $ρN$ forward scattering amplitude. This amplitude is derived from a relativistic resonance model. In comparison to previous non-relativistic calculations we find a much weaker momentum dependence of $Σ_{med}$, especially in the transverse channel. Special attention is paid to uncertainties in the model. Thus, we compare the impact of different coupling schemes for the $RNρ$ interaction on the results and discuss various resonance parameter sets.

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M. Post, S. Leupold, U. Mosel. 2001-01-09. The $ρ$ Spectral Function in a Relativistic Resonance Model. https://doi.org/10.1016/s0375-9474(00)00613-8

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