Implications Of A Fully Nonlocal Implementation Of The Dispersive Optical Model

A fully nonlocal treatment for the dispersive optical model (DOM) is implemented for both the real and imaginary part of the self-energy inspired by ab initio theoretical calculations of this quantity. By means of the dispersion relation between the real and imaginary part of the optical potential a link between the energy domain of nuclear reactions and nuclear structure is established. The relevant scattering data for neutrons and protons on 40Ca are described with the same quality as was accomplished with previous local versions of the DOM. The solution of the Dyson equation at positive and negative energies is generated with a complete treatment of the nonlocality of the potentials. The resulting propagator has been utilized to explain and predict relevant quantities of the ground-state of the 40Ca nucleus. In particular the charge density, spectral strength and particle number can, for the first time, be accurately described. Moreover, due to the introduction of nonlocality in the imaginary part of the self-energy it is also possible to describe high-momentum protons and the contribution of the two-body interaction to the ground-state energy. The calculation of the spectral density at positive energies allows for the determination of the spectral strength of mostly occupied single-particle orbits in the continuum. Consistency of the resulting depletion numbers with the corresponding occupation numbers is studied and compared to ab initio calculations for these quantities. Starting from the 40Ca self-energy, an extension to the 48Ca nucleus is implemented focusing on the N-Z dependence of the nucleon self-energy. Neutron scattering data can be described with even better quality than previous local DOM calculations. The scattering properties for protons are of similar excellent quality as for previous local results. From the solution of the Dyson equation for neutrons it is possible to calculate the neutron distribution of this nucleus allowing for the determination of the neutron skin which is relevant for the physics of neutron stars. The resulting value is larger than most calculations previously reported including an ab initio one. An argument supporting a large neutron skin is provided by analyzing proton elastic scattering data on both 40Ca and 48Ca.

This thesis develops the dispersive optical model into a tool that allows for the assessment of the validity of nuclear reaction models, thereby generating unambiguous removal probabilities of nucleons from valence orbits using the electron-induced proton knockout reaction. These removal probabilities document the substantial quantitative degree in which nuclei deviate from the independent-particle model description. Another outcome reported within is the prediction for the neutron distribution of Ca-40, Ca-48, and Pb-208. The neutron radii of these nuclei have direct relevance for the understanding of neutron stars and are currently the subject of delicate experiments. Unlike other approaches, the current method is consistent with all other relevant data and describes nuclei beyond the independent-particle model. Finally, a new interpretation of the saturation probabilities of infinite nuclear matter is proposed suggesting that the semi-empirical mass formula must be supplemented with a better extrapolation from nuclei to infinite matter.

Advances in photonics and nanotechnology have the potential to revolutionize humanitys ability to communicate and compute. To pursue these advances, it is mandatory to understand and properly model interactions of light with materials such as silicon and gold at the nanoscale, i.e., the span of a few tens of atoms laid side by side. These interactions are governed by the fundamental Maxwells equations of classical electrodynamics, supplemented by quantum electrodynamics. This book presents the current state-of-the-art in formulating and implementing computational models of these interactions. Maxwells equations are solved using the finite-difference time-domain (FDTD) technique, pioneered by the senior editor, whose prior Artech House books in this area are among the top ten most-cited in the history of engineering. This cutting-edge resource helps readers understand the latest developments in computational modeling of nanoscale optical microscopy and microchip lithography, as well as nanoscale plasmonics and biophotonics.

This book presents the latest results of quantum properties of light in the nanostructured environment supporting surface plasmons, including waveguide quantum electrodynamics, quantum emitters, strong-coupling phenomena and lasing in plasmonic structures. Different approaches are described for controlling the emission and propagation of light with extreme light confinement and field enhancement provided by surface plasmons. Recent progress is reviewed in both experimental and theoretical investigations within quantum plasmonics, elucidating the fundamental physical phenomena involved and discussing the realization of quantum-controlled devices, including single-photon sources, transistors and ultra-compact circuitry at the nanoscale.

This workshop series was established to explore the theoretical motivations for the Facility of Rare Isotope Beams. This specific workshop focused on bulk nuclear quantities and included discussions of nuclear masses, ab-initio nuclear structure, nuclear energy functional, giant resonances, nuclear matter, nuclear equation of state, central collisions and neutron stars.

The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners.