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Interaction of vector mesons with baryons and nuclei

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 نشر من قبل Eulogio Oset
 تاريخ النشر 2012
  مجال البحث
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After some short introductory remarks on particular issues on the vector mesons in nuclei, in this paper we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei from a modern perspective using the local hidden gauge formalism for the interaction of vector mesons. We present results for the vector baryon interaction and in particular for the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons, taking also the mixing of these states with pseudoscalars and baryons into account. We then venture into the charm sector, reporting on hidden charm baryon states around 4400 MeV, generated from the interaction of vector mesons and baryons with charm, which have a strong repercussion on the properties of the $J/Psi N$ interaction. We also address the interaction of $K^*$ with nuclei and make suggestions to measure the predicted huge width in the medium by means of the transparency ratio. The formalism is extended to study the phenomenon of $J/psi$ suppression in nuclei via $J/psi$ photoproduction reactions.



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In this talk we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei. We begin with the hidden gauge formalism for the interaction of vector mesons, then review results for vector bary on interaction and in particular the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons. New developments concerning the mixing of these states with pseudoscalars and baryons are also reported. We include some discussion on the $5/2^+$ $Delta$ resonances around 2000 MeV, where we suggest that the $Delta(2000)5/2^+$ resonance, which comes in the PDG from averaging a set of resonances appearing around 1700 MeV and another one around 2200 MeV, corresponds indeed to two distinct resonances. We also report on a hidden charm baryon state around 4400 MeV coming from the interaction of vector mesons and baryons with charm, and how this state has some repercussion in the $J/psi$ suppression in nuclei. The interaction of $K^*$ in nuclei is also reported and suggestions are made to measure by means of the transparency ratio the huge width in the medium that the theoretical calculations predict. The formalism is extended to $J/psi$ interaction with nuclei and the transparency ratio for $J/psi$ photoproduction in nuclei is studied and shown to be a good tool to find possible baryon states which couple to $J/psi N$.
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