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Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in Coherent Photo- and Electroproduction: Coupled Channel Analysis

N. N. Nikolaev·J. Speth·B. G. Zakharov
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Abstract

We study medium modifications of the dilepton mass spectrum in coherent photo- and electroproduction of the Rho(1S)- and Rhoprim(2S)-meson resonances on nuclear targets. The analysis is performed within the coupled Rho, Rhoprim... channel formalism in which nuclear modifications derive from the off-diagonal rescatterings. We find that the effect of off-diagonal rescatterings on the shape of the dilepton mass spectrum in the Rho(1S)-meson mass region is only marginal but is very important in the Rhoprim mass region. The main off-diagonal contribution in the Rhoprim mass region comes from the sequential mechanism gamma* -> Rho -> Rhoprim(2S), which dominates the Rhoprim(2S) production for heavy nuclei. Our results show also that in the Rhoprim(2S) mass region there is a considerable effect of the interference of the Breit-Wigner tail of Rho(1S)-meson with the Rhoprim-meson.

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N. N. Nikolaev, J. Speth, B. G. Zakharov. 1999-09-29. Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in Coherent Photo- and Electroproduction: Coupled Channel Analysis. https://doi.org/10.1134/1.1307468

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