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تسجيل مستخدم جديدLippmann-Schwinger Resonating-Group Formalism for NN and YN Interactions in an SU6 Quark Model
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Yoshikazu Fujiwara
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We formulate a Lippmann-Schwinger-type resonating-group equation to calculate invariant amplitudes of the quark-model baryon-baryon interaction. When applied to our recent SU6 quark model for the nucleon-nucleon and hyperon-nucleon interactions, this technique yields very accurate phase-shift parameters for all partial waves up to the energies of several GeV. The technique also has a merit of a straightforward extension to the G-matrix equation. A new analytic method is proposed to calculate the quark-exchange Born kernel for the momentum-dependent two-body interaction. The partial-wave decomposition in the momentum representation is carried out numerically. The invariant amplitudes are then used to calculate single-nucleon potentials in normal nuclear matter for high incident momenta q_1 > 3 (1/fm), in which the so-called t^eff-rho prescription is found to be a good approximation to the single-particle potentials directly calculated in the lowest-order Brueckner theory.
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We calculate n alpha phase-shifts and scattering observables in the resonating-group method, using the nuclear-matter G-matrix of an SU_6 quark-model NN interaction. The G-matrix is generated in the recent energy-independent procedure of the quark-mo
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