الفهرس 
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Abstract
The problem of the short range part of the nuclear force for nonstrange baryons (only up and down quarks with three color states) in a nonrelativistic quark model is studied by the resonating group method. The up and down quarks are assumed to have a common mass and are considered to form a fundamental representation of the spin (S)-isospin (T) SU (4) group. It is assumed that quarks interact with each other by a two-body local potential, which confines the quark in color singlet system and also has the effect of one gluon exchange between the quarks. We introduced four different types of the central interactions between the quarks: Coulombian, oscillator, delta and momentum dependent potentials. The interactions between quarks which depend on their spins are the spin-spin, spin-orbit and tensor types. The long-range dominant part is the confinement quadratic harmonic oscillator potential. The coupling constants and the quark mass in various channels have been determined by optimized method which is required from the analysis of baryon-baryon scattering. The one gluon exchange confining constants have been reliably determined from the masses of the S-wave baryons, and their consistency with some other S-wave baryonic data also been checked.
The orbital space is discussed and the relation between the symmetry classification and the particle classification of the two-baryon states are studied. The calculated phase shifts for the 3S1(S=1, T=0) and 1S0 (S=0, T=1) states of two nucleons indicate the presence of strong repulsive force (repulsive core) at short distance due to a color magnetic interaction, while an attractive force is predicted for the 7S3(ΔΔ) (S=3, T=0) of two Δ’s. The short range repulsion between two nucleons was understood as a combined effect of the pauli principle and the spin-spin term of the one gluon exchange interaction between quarks. We have found that the Δ-Δ and colored baryon- colored baryon channels make important contributions to the NN channel.
The proposed quark model is suitable only for short range part of baryon- baryon interaction and does not give attraction in the intermediate and long range parts.
For describing intermediate and long parts of nucleon-nucleon interaction, we suggested two theoretical nonrelativistic potential models in framework of meson exchange theory.
The first model is soft core potential; it contains central, spin-spin, tensor, spin-orbit and quadratic spin-orbit terms with Yukawa radial dependence. Each of the independent terms is composed of four Yukawa potentials multiplied by a correction function.
The optimized potential parameters are adjusted for singlet even and triplet odd states by using a computer simulation search program to fit the calculated phase shifts with the experimental nucleon-nucleon data.
The second model is repulsive core potential to investigate the central force for the deuteron (p n); it consists of long range attractive exponential part and a short repulsive Yukawa part. The parameters of the second model are adjusted to investigate the binding energy of the deuteron.