We report microscopic calculations of the equation of state of symmetric nuclear matter and the nucleon-nucleus optical potential in the Brueckner-Hartree-Fock approach. The calculations use several internucleon (NN) potentials, such as the Hamada-Johnston, Urbana v14, Argonne v14, Argonne v18, Reid93, and Nijm II along with and without two types of three-body forces (TBFs): the Urbana IX model and the phenomenological density-dependent three-nucleon interaction model of Lagris and Pandharipande [Nucl. Phys. A 359, 349 (1981)] and Friedman and Pandharipande [Nucl. Phys. A 361, 502 (1981)]. The inclusion of TBFs helps to reproduce the saturation properties for symmetric nuclear matter rather well as expected. The proton-nucleus optical potential has been calculated by folding the calculated reaction matrices (with and without three-body forces) over the nucleon density distributions obtained from the relativistic mean-field theory. The results show that the inclusion of TBFs reduces the strength of the central part of the optical potential in the nuclear interior and affects the calculated spin-orbit potential only marginally. As a test of the calculated potential, we have analyzed proton differential elastic scattering, analyzing power, and spin-rotation data from 40 Ca and 208 Pb at 65 and 200 MeV. It is observed that the inclusion of TBFs improves the agreement with the experiment especially for the polarization data.

Microscopic optical potentials for nucleon-nucleus scattering obtained from folding the calculated G-matrices with RMF densities of the target have been used to analyze the 65 MeV proton and neutron-nucleus scattering data over a wide mass region. The soft-core Argonne AV14, AV18 and the old hard-core Hamada-Johnston inter-nucleon potentials have been used to calculate the Gmatrices in the Brueckner-Hartree-Fock approach. The calculated potentials have been used to analyze the differential elastic cross-section, analyzing power and spin-rotation function for neutron and proton scattering at 65 MeV from 12 C to 208 Pb. Our results are in satisfactory agreement with the experimental data. Comparison of our results with phenomenological optical model analyses is also presented. Mass number dependence of the mean square radii of real central optical potential r 2 pot. for the microscopic potentials used here is found to be in close agreement with each other as well as with empirical results. We also present our results for proton reaction cross-section from 12 C to 90 Zr in the energy region 20-200 MeV.

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In the present work we describe our results concerning the calculation of equation of state of symmetric zero temperature nuclear matter and the microscopic optical potential using the soft-core Argonne inter-nucleon potentials in first order Brueckner–Hartree–Fock (BHF) theory. The nuclear matter saturates at a density 0.228 nucleon/fm 3 with 17.52 MeV binding energy per nucleon for Argonne av-14 and at 0.228 nucleon/fm 3 with 17.01 MeV binding energy per nucleon for Argonne av-18. As a test case we present an analysis of 65 and 200 MeV protons scattering from 208 Pb . The Argonne av-14 has been used for the first time to calculate nucleon optical potential in BHF and analyze the nucleon scattering data. We also compare our reaction matrix results with those using the old hard-core Hamada–Johnston and the soft-core Urbana uv-14 and Argonne av-18 inter-nucleon potentials. Our results indicate that the microscopic potential obtained using av-14 gives marginally better agreement with the experimental data than the other three Hamiltonians used in the present work.

We have shown that the commonly used series expansion given by Greenlees et al. and Scheerbaum for calculating the spin-orbit potential is not rapidly convergent and that exact calculation of the dominant direct part can be easily done. Our exact calculation of the microscopic optical potential for the scattering of protons from 40 Ca and 208 Pb at 65 MeV and 200 MeV shows that the direct part is substantially different from the results using series expansion. Our results show that the spin-orbit potential affects the cross-section even at intermediate angles specially at high energies. The results presented here have direct application for calculating spin-orbit potential of all strongly interacting Fermionic probes.