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The binding energy per nucleon for nuclear matter, i.e., equation of state (EOS), within the Brueckner–Hartree–Fock (BHF) approach with the consideration of various three-body forces (3BFs) like the phenomenological 3BF and by adding a contact term to the BHF calculations are considered at variance densities. The 3BF contribution turns out to be nonnegligible contribution and to have a substantial saturation effect. The calculations are done utilizing the CD-Bonn and Argonne V18 nucleon–nucleon (NN) potentials. These NN potentials give great fitting to the deuteron properties and are phase-shift equivalent. The resultant EOS is compatible with the phenomenological analysis on the saturation point. It is demonstrated that the 3BF influences significantly on the nuclear matter EOS at high densities. Moreover, it is necessary for reproducing the empirical saturation properties for symmetric nuclear matter. The pressure has been also calculated and the suggested approaches reproduce fairly well agreement with the empirical data. We also examined the maximum neutron star masses which are close to two solar masses, which is again compatible with recent observational data. Comparison with other microscopic EOS is presented and discussed.

The spin response of the $$\vec{\gamma}\vec{d}\to\pi^{0}d$$ reaction near threshold is investigated. Our formalism based on the impulse approximation, uses the realistic Bonn $$NN$$ potential (full model) for the deuteron wave function and the unitary isobar MAID-2007 model for the elementary $$\gamma N\to\pi N$$ amplitude. We present the first results for the double polarized differential and total cross sections for parallel and antiparallel helicity states, the deuteron spin asymmetry, the helicity $$E$$ -asymmetry, the deuteron GDH integral, and the double spin asymmetries of the total cross section in the near-threshold region. Sensitivity of the estimated results to the $$D$$ -wave effect of the deuteron wave function for a realistic $$NN$$ potential is studied. We find an insignificant sensitivity of most of the estimated observables to the $$D$$ -wave component. A noticeable role is obtained only in the double polarized differential cross section with antiparallel spins of photon and deuteron $$d\sigma^{A}/d\Omega_{\pi}$$ close to the threshold energy at forward and backward pion angles as well as in the double spin asymmetry of the total cross section $$\sigma\tilde{T}_{20}$$ at relatively large photon energies. Thus, we compare results for these two observables using various $$NN$$ potential models with different $$D$$ -state probabilities, and a noticeable influence is found.

Influence of nucleon structure on single tensor-deuteron and double beam-vector-deuteron analyzing powers in the elastic electron-deuteron scattering process is investigated. We report numerical results for the tensor-deuteron (T20, T21, and T22), and beam-vector-deuteron (T10 and T11) analyzing powers as functions of the four-momentum transfer square Q2 and the electron scattering angle in the laboratory frame θe. This is made possible with the advent of recent polarization measurements with polarized electron beams and/or polarized deuteron targets at MIT-Bates, JLab, NIKHEF, VEPP-2, and VEPP-3. We found that the predicted results for T21, T22, T10, and T11 are sensitive to the nucleon electromagnetic form factors. On the contrary, the T20 analyzing power is found to be almost independent on the actual nucleon form factors. The predicted analyzing powers are compared with the available experimental data and a satisfactory agreement is obtained.