Modern approaches to optical potentials

Abstract

In this chapter we will give an overview of the optical model description of nucleon-nucleus scattering and reactions based on fundamental nuclear two-body and many-body forces. We begin with a short overview followed by several commonly used theoretical techniques for deriving nucleon-nucleus optical model potentials that account for antisymmetry, Pauli blocking, and multiple scattering. We then summarize current efforts to derive microscopic nuclear forces consistent with the fundamental theory of strong interactions, quantum chromodynamics, and the use of such interactions in the construction of microscopic optical potentials. We also outline the dispersive optical potential approach, which despite being primarily phenomenological, has its origins in formal Green's function theory. Finally, we benchmark the results from modern optical potentials to experimental data.

Dense Nuclear Matter Equation of State from Heavy-Ion Collisions

“…MBPT also allows us to study nuclear properties other than the nuclear EOS, including the linear response and transport coefficients that could be used to inform more accurate numerical simulations of supernovae and neutron-star mergers [207]. Furthermore, MBPT for (infinite) nuclear matter has been used to construct a microscopic global optical potential with quantified uncertainties based on χEFT NN and 3N interactions [208,209]. Altogether, MBPT calculations of nuclear matter properties can provide important constraints that enable microscopic interpretations of future nuclear reaction experiments [210] (e.g., at the Facility for Rare Isotope Beams) and neutron star observations.…”

Optical potentials for the rare-isotope beam era

“…The nuclear matter approach also tends to produce an overly absorptive imaginary term at high energies. Some of these shortcomings may be straightforwardly remedied while for others the solution remains unclear, for more details see [313]. Ultimately, the quality of theoretical predictions for reaction cross sections from optical potentials derived within the nuclear matter approach must be assessed by comparisons to experimental data.…”