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Mass and width of the $d'$ resonance in nuclei

A. Valcarce·F. Fernandez·H. Garcilazo
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Abstract

We calculated the mass and width of the $d'$ resonance inside nuclei within a nucleon-$Δ$ model by including the self-energy of the $Δ$ in the $NΔ$ propagator. We found that in the nuclear medium the width of the $d'$ is increased by one order of magnitude while its mass changes only by a few MeV. This broadening of the width of the $d'$ resonance embedded in nuclei is consistent with the experimental observations so that the $d'$ can be understood as a $NΔ$ resonance. Thus, given the freedom between either isospin 0 or isospin 2 for the $d'$, our results give weigth to the isospin-2 assignment.

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A. Valcarce, F. Fernandez, H. Garcilazo. 1996-06-19. Mass and width of the $d'$ resonance in nuclei. https://doi.org/10.1103/physrevc.54.1010

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