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Pionic decay of a possible d'-dibaryon and the short-range NN interaction

I. T. Obukhovsky·K. Itonaga·Georg Wagner·A. J. Buchmann·Amand Faessler
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Abstract

We study the pionic decay of a possible dibaryon d' --> N N πin the microscopic quark shell model. The initial d' dibaryon wave function (J^P=0^-, T=0) consists of one 1\hbarωsix-quark shell-model s^5p[51]_X configuration. The most important final six-quark configurations s^6[6]_X, s^4p^2[42]_X and (s^4p^2-s^52s)[6]_X are properly projected onto the NN channel. The final state NN interaction is investigated by means of two phase-equivalent - but off-shell different - potential models. We demonstrate that the decay width Γ_d' depends strongly on the short-range behavior of the NN wave function. In addition, the width Γ_d' is very sensitive to the mass and size of the d' dibaryon. For dibaryon masses slightly above the experimentally suggested value M_d'=2.065 GeV, we obtain a pionic decay width of Γ_d' = 0.18 - 0.32 MeV close to the experimental value Γ_d' = 0.5 MeV.

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I. T. Obukhovsky, K. Itonaga, Georg Wagner, A. J. Buchmann, Amand Faessler. 1997-08-29. Pionic decay of a possible d'-dibaryon and the short-range NN interaction. https://doi.org/10.1103/physrevc.56.3295

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