Mass-number and isotope dependence of local microscopic optical potentials for polarized proton scattering

Abstract

We derive local microscopic optical potentials U systematically for polarized proton scattering at 65 MeV using the local-potential version of the Melbourne g-matrix folding model. As target nuclei, we take 6 He and neutron-rich Ne isotopes in addition to stable nuclei of mass number A = 4-208 in order to clarify mass-number and isotope dependence of U . The local potentials reproduce the experimental data systematically and have geometries similar to the phenomenological optical potentials for stable targets. The target density is broadened by the weak-binding nature and/or deformation of unstable nuclei. For the real spin-orbit part of U the density broadening weakens the strength and enlarges the radius, whereas for the central part it enlarges both of the strength and the radius. The density-broadening effect is conspicuous for halo nuclei such as 6 He and 31 Ne. Similar discussions are made briefly for proton scattering at 200 MeV. We briefly investigate how the isovector and the non spherical components of U affect proton scattering.

Ground-state properties of neutron-rich Mg isotopes

“…Recently, Nakamura et al [16] suggested through measurements of the one-neutron removal cross section of 31 Ne on C and Pb targets at 240 MeV/nucleon that 31 Ne is a halo nucleus that resides in the island of inversion. Takechi et al [17] measured σ I for Ne isotopes incident on 12 C targets at 240 MeV/nucleon and came to the same conclusion as Nakamura et al Very recently, Takechi et al measured σ R for [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] Mg isotopes on C targets at 240 MeV/nucleon [18] and suggested that 37 Mg is a halo nucleus.…”

“…For nucleon scattering from stable target nuclei, the folding potential with the Melbourne g-matrix interaction reproduces measured elastic and reaction cross sections systematically with no adjustable parameter [26,29]. The folding model is reliable also for the scattering of unstable nuclei from stable target nuclei at intermediate incident energies, say 200 MeV/nucleon, since the projectile breakup is small there.…”

“…A powerful tool of analyzing measured σ R or σ I microscopically is the folding model with the g-matrix effective nucleon-nucleon interaction [19][20][21][22][23][24][25][26][27][28][29]. For nucleon scattering from stable target nuclei, the folding potential with the Melbourne g-matrix interaction reproduces measured elastic and reaction cross sections systematically with no adjustable parameter [26,29].…”

Nuclear data evaluation of long-lived fission products: Microscopic vs. phenomenological optical potentials

“…It was also confirmed that the optical potential can reproduce experimentally measured elastic scattering cross sections from light to heavy nuclei successfully if the density distributions of target nuclei are correctly given [3]. In addition, Toyokawa et al also investigated elastic scattering cross sections of several nuclei with polarized protons with this potential [4]. The optical potentials are derived from the nucleon-nucleus folding model with the g-matrix of the Melbourne interaction [5] constructed from the Bonn-B NN interaction [6].…”

Fully microscopic description of elastic and inelastic scattering at intermediate incident energies

“…They applied a g-matrix interaction constructed with the Bonn potential [4] to the folding model calculation, and reproduced the measured elastic cross sections and vector analyzing powers in a wide incident-energy range [5]. In addition, the Melbourne interaction was also applied to neutron scattering [6] and scattering of weakly-bound nucleus [7,8]. Furthermore, total reaction cross sections of scattering of stable and unstable nuclei were well reproduced [9,10].…”