Manchester Nuclear Physics Consolidated Grant Request

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Nuclear Physics aims to understand the structure and dynamics of nuclear systems. It is the key to understanding the Universe from the first microseconds of its inception when the quark-gluon plasma prevailed, through its history of star and galaxy formation where nuclear reactions play an essential role both in the generation of energy and the creation of elements. The field also has applications that benefit society in diverse areas, from medicine and security to power production, and a strong impact on other fields of science.Atomic nuclei are a unique quantal laboratory in which microscopic as well as mesoscopic features, driven by effective two-body and three-body forces, can be studied. They are complex many-body systems, but often display unexpected regularities and simple excitation patterns that arise from underlying shell structure, pairing and collective modes of excitation. Such properties are also exhibited by simpler mesoscopic systems (for example, metallic clusters, quantum dots, and atomic condensates) the understanding of which draws heavily on techniques developed and honed in nuclear physics. A fundamental challenge is to understand nuclear properties ab-initio from the interplay of the strong, weak, and electromagnetic forces between individual nucleons. In recent years, enormous progress has been made with such programmes for light nuclei. For heavier nuclei, shell, cluster and other beyond mean field many-body techniques, based on effective interactions, provide essential frameworks for correlating experimental data, yet still lack the refinement to reliably predict nuclear properties as one moves more than a few nucleons from well-studied stable nuclei.We plan to make measurements of transfer reactions, particle and gamma decays, state lifetimes, ground-state and isomer properties using lasers, and neutron-induced reactions to yield data with which to study the development of nuclear shapes, the evolution of nuclear structure in exotic isotopes and the reactions important for the s and r nucleosynthetic pathways. We also aim to make connections between the interactions of nucleons and the underlying theory that describes the strong force, Quantum Chromodynamics. Key quantities are the polarisabilities that describe how the structures of nucleons respond to external electric and magnetic fields. We are developing theoretical tools to determine these from experiments on the scattering of photons from hydrogen and other light nuclei. The latter are needed to learn about the the properties of the neutron since it is an unstable particle, and are also interesting for the testing of nuclear forces in few-body systems and for the calculation of muonic atom Lamb shifts.See the Case for Support for more details about the proposed research.