Irreducible nonlocality of optical model potentials based on realistic NN interactions

Abstract

We investigate the nonlocal structure of optical model potentials for nucleon-nucleus scattering based on microscopic approaches. To this purpose, \emph{in-medium} folding optical potentials are calculated in momentum space and their corresponding coordinate-space counterpart are examined, paying special attention to their nonlocal shape. The nucleon-nucleon effective interaction consists of the actual full off-shell $g$ matrix in Brueckner-Hartree-Fock approximation. The nonlocality of effective interactions is preserved throughout all stages in the the calculation. Argonne $v_{18}$ bare potential and chiral next-to-next-to-next-to-leading order bare interaction are used as starting point. The study is focused on proton elastic scattering off ${}^{40}$Ca at beam energies between 30 and 800 MeV. We find that the gradual suppression of high-momentum contributions of the optical potential results in quite different-looking coordinate-space counterparts. Despite this non-uniqueness in their nonlocal structure, the implied scattering observables remain unchanged for momentum cutoff above a critical one, which depends on incident energy of the projectile. We find that coordinate-space potentials with momentum cutoffs at the critical value yield the least structured nonlocal behavior. Implications of these findings are discussed.

14 pages; 16 figures. Submitted to PRC

References in corpus (5)

• Optical potential from first principles
• Microscopic positive-energy potential based on Gogny interaction
• Low-density homogeneous symmetric nuclear matter: disclosing dinucleons in coexisting phases
• Surface-peaked medium effects in the interaction of nucleons with finite nuclei
• An in-medium full-folding model approach to quasielastic (p,n) charge-exchange reactions

Cited by in corpus (11)

• Optical potentials for the rare-isotope beam era
• Uncertainty-quantified phenomenological optical potentials for single-nucleon scattering
• Impact of Three-Body Forces on Elastic Nucleon-Nucleus Scattering Observables
• SWANLOP : Scattering waves off nonlocal optical potentials in the presence of Coulomb interactions
• Exact scattering waves off nonlocal potentials under Coulomb interaction within Schrödinger's integro-differential equation
• Elastic Antiproton-Nucleus Scattering from Chiral Forces
• Ultraviolet suppression and nonlocality in optical model potentials for nucleon-nucleus scattering
• Coupled-cluster computations of optical potential for medium-mass nuclei
• Nonlocal structure of the leading order \textit{ab initio} effective potentials for proton elastic scattering from light nuclei
• Elastic proton scattering off non-zero spin nuclei
• Microscopic optical potentials from a Greens function approach