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تسجيل مستخدم جديدThe Delta N -> NN transition in finite nuclei
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We perform a direct finite nucleus calculation of the partial width of a bound Delta isobar decaying through the non-mesonic decay mode, Delta N -> NN. This transition is modeled by the exchange of the long ranged pi meson and the shorter ranged rho meson. The contribution of this decay channel is found to be approximately 60 % of the decay width of the Delta particle in free space. Considering the additional pionic decay mode, we conclude that the total decay width of a bound Delta resonance in nuclei is of the order of 100 MeV and, consequently, no narrow Delta nuclear states exist, contrary to recent claims in the literature. Our results are in complete agreement with microscopic many-body calculations and phenomenological approaches performed in nuclear matter.
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