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تسجيل مستخدم جديدThe d-Dibaryon in the Nonrelativistic Quark Model
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The narrow peak recently found in various pionic double charge exchange (DCX) cross sections can be explained by the assumption of a universal resonance at 2065 MeV, called d. We calculate the mass of a six-quark system with J^P=0^-, T=0 quantum numbers employing a cluster model and a shell model basis to diagonalize the nonrelativistic quark model Hamiltonian.
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We calculate the mass and structure of a J^P=0^-, T=0 six-quark system using a colored diquark-tetraquark cluster wave function and a nonrelativistic quark model Hamiltonian. The calculated mass is some 350 MeV above the empirical value if the same c
onfinement strength as in the nucleon is used. If the effective two-body confinement strength is weaker in a compound six-quark system than in a single baryon, as expected from a simple harmonic oscillator model, one obtains M_d = 2092 MeV close to experiment.
The mass and wave function of a six-quark system with quantum numbers J^P=0^-, T=0, called d, are calculated. We use a colored diquark-tetraquark cluster model for the six-quark wave function. A constituent quark model Hamiltonian with a two-body con
finement potential, and residual one-gluon, one-pion, and one-sigma exchange interactions is used. The complications due to the quark exchange interactions between tetraquark and diquark clusters (Pauli principle) are taken into account within the framework of the Resonating Group Method. The calculated d mass is some 350 MeV above the empirical value if the same two-body confinement strength as in the nucleon and Delta is used. This paper also examines the validity of the usual assumption of a universal two-quark confinement strength. We propose that the effective two-body confinement strength in an exotic six-quark system, such as the d, could be weaker than in a single baryon. The weaker confinement hypothesis leads to a d mass of M=2092 MeV and a d radius of r=1.53 fm.
Charmed dibaryon states with the spin-parity $J^{pi}=0^+$, $1^+$, and $2^+$are predicted for the two-body $Y_cN$ ($=Lambda_c$, $Sigma_c$, or $Sigma^*_c$) systems. We employ the complex scaling method for the coupled channel Hamiltonian with the $Y_cN
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There exists experimental evidence that a dibaryon resonance d with quantum numbers J^P=0^-,T=0 and mass 2065 MeV could be the origin of the narrow peak in the (pi^+ ,pi^- ) double charge exchange cross--sections on nuclei. We investigate the six--qu
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