Nuclear Structure and Reactions: Theory and Experiment
Lead Research Organisation:
University of Surrey
Department Name: Physics
Abstract
Nuclear physics research is undergoing a transformation. For a hundred years, atomic nuclei have been probed by collisions between stable beams and stable targets, with just a small number of radioactive isotopes being available. Now, building on steady progress over the past 20 years, it is at last becoming possible to generate intense beams of a wide range of short-lived isotopes, so-called "radioactive beams". This enables us vastly to expand the scope of experimental nuclear research. For example, it is now realistic to plan to study in the laboratory a range of nuclear reactions that take place in exploding stars. Thereby, we will be able to understand how the chemical elements that we find on Earth were formed and distributed through the Universe.
At the core of our experimental research is our strong participation at leading international radioactive-beam facilities. While we are now contributing, or planning to contribute, to substantial technical developments at these facilities, the present grant request is focused on the exploitation of the capabilities that are now becoming available.
Experimental progress is intimately linked with theory, where novel and practical approaches are a hallmark of the Surrey group. An outstanding feature, which is key to our group's research plans and is unique in the UK, is our powerful blend of theoretical and experimental capability.
Our science goals are aligned with current STFC strategy for nuclear physics, as expressed in detail through the Nuclear Physics Advisory Panel. We wish to understand the boundaries of nuclear existence, i.e. the limiting conditions that enable neutrons and protons to bind together to form nuclei. Under such conditions, the nuclear system is in a delicate state and shows unusual phenomena. It is very sensitive to the properties of the nuclear force. For example, weakly bound neutrons can orbit their parent nucleus at remarkably large distances. This is already known, and our group made key contributions to this knowledge. What is unknown is whether, and to what extent, the neutrons and protons can show different collective behaviours. Also unknown, for most elements, is how many neutrons can bind to a given number of protons. It is features such as these that determine how stars explode. To tackle these problems, we need a more sophisticated understanding of the nuclear force, and we need experimental information about nuclei with unusual combinations of neutrons and protons to test our theoretical ideas and models. Therefore, theory and experiment go hand-in-hand as we push forward towards the nuclear limits.
An overview of nuclear binding reveals that about one half of predicted nuclei have never been observed, and the vast majority of this unknown territory involves nuclei with an excess of neutrons. Much of our activity addresses this "neutron-rich" territory, exploiting the new capabilities with radioactive beams.
Our principal motivation is the basic science, and we contribute strongly to the world sum of knowledge and understanding. Nevertheless, there are more-tangible benefits. For example, our radiation-detector advances can be incorporated in medical diagnosis and treatment. In addition, we provide an excellent training environment for our research students and staff, many of whom go on to work in the nuclear power industry, helping to fill the current skills gap. On a more adventurous note, our special interest in nuclear isomers (energy traps) could lead to novel energy applications. Furthermore, we have a keen interest in sharing our specialist knowledge with a wide audience, and we already have an enviable track record with the media.
At the core of our experimental research is our strong participation at leading international radioactive-beam facilities. While we are now contributing, or planning to contribute, to substantial technical developments at these facilities, the present grant request is focused on the exploitation of the capabilities that are now becoming available.
Experimental progress is intimately linked with theory, where novel and practical approaches are a hallmark of the Surrey group. An outstanding feature, which is key to our group's research plans and is unique in the UK, is our powerful blend of theoretical and experimental capability.
Our science goals are aligned with current STFC strategy for nuclear physics, as expressed in detail through the Nuclear Physics Advisory Panel. We wish to understand the boundaries of nuclear existence, i.e. the limiting conditions that enable neutrons and protons to bind together to form nuclei. Under such conditions, the nuclear system is in a delicate state and shows unusual phenomena. It is very sensitive to the properties of the nuclear force. For example, weakly bound neutrons can orbit their parent nucleus at remarkably large distances. This is already known, and our group made key contributions to this knowledge. What is unknown is whether, and to what extent, the neutrons and protons can show different collective behaviours. Also unknown, for most elements, is how many neutrons can bind to a given number of protons. It is features such as these that determine how stars explode. To tackle these problems, we need a more sophisticated understanding of the nuclear force, and we need experimental information about nuclei with unusual combinations of neutrons and protons to test our theoretical ideas and models. Therefore, theory and experiment go hand-in-hand as we push forward towards the nuclear limits.
An overview of nuclear binding reveals that about one half of predicted nuclei have never been observed, and the vast majority of this unknown territory involves nuclei with an excess of neutrons. Much of our activity addresses this "neutron-rich" territory, exploiting the new capabilities with radioactive beams.
Our principal motivation is the basic science, and we contribute strongly to the world sum of knowledge and understanding. Nevertheless, there are more-tangible benefits. For example, our radiation-detector advances can be incorporated in medical diagnosis and treatment. In addition, we provide an excellent training environment for our research students and staff, many of whom go on to work in the nuclear power industry, helping to fill the current skills gap. On a more adventurous note, our special interest in nuclear isomers (energy traps) could lead to novel energy applications. Furthermore, we have a keen interest in sharing our specialist knowledge with a wide audience, and we already have an enviable track record with the media.
Planned Impact
Here we address more specifically the wider community who may benefit from our basic research.
A key current topic is that of nuclear security. Here our advanced experimental and theoretical techniques may help to address the needs of the security industry. In this regard we are well connected with AWE plc, including collaborative PhD students.
We have recently developed strong links with the National Physical Laboratory, where we enhance their capabilities in radionuclide metrology.
Sustainable energy production is another vital issue for society, and nuclear energy has an important role to play. We have made fundamental advances that lead to a better understanding of decay heat in nuclear reactors. Furthermore, our basic studies of both reaction processes and the structure of unstable nuclei may be important for future nuclear energy technologies.
Cancer diagnosis and treatment is of great importance. Our radiation-detector advances can lead to improved imaging systems, that benefit cancer and other medical treatments.
A key current topic is that of nuclear security. Here our advanced experimental and theoretical techniques may help to address the needs of the security industry. In this regard we are well connected with AWE plc, including collaborative PhD students.
We have recently developed strong links with the National Physical Laboratory, where we enhance their capabilities in radionuclide metrology.
Sustainable energy production is another vital issue for society, and nuclear energy has an important role to play. We have made fundamental advances that lead to a better understanding of decay heat in nuclear reactors. Furthermore, our basic studies of both reaction processes and the structure of unstable nuclei may be important for future nuclear energy technologies.
Cancer diagnosis and treatment is of great importance. Our radiation-detector advances can lead to improved imaging systems, that benefit cancer and other medical treatments.
Organisations
Publications
Browne F
(2015)
Gamma-ray Spectroscopy in the Vicinity of $^{108}$Zr
in Acta Physica Polonica B
Alexander T
(2015)
Isomeric Ratios in $^{206}$Hg
in Acta Physica Polonica B
Sethi J
(2015)
Spectroscopy of the Low-lying States Near the High Spin Isomer in $^{108}$Ag
in Acta Physica Polonica B
Goigoux T
(2019)
$^{67}$Kr Two-proton Radioactivity: Results and Theoretical Interpretations
in Acta Physica Polonica B
Rudigier M
(2019)
Isomer Spectroscopy and Sub-nanosecond Half-live Determination in $^{178}$W Using the NuBALL Array
in Acta Physica Polonica B
Jones K
(2015)
Recent Direct Reaction Experimental Studies with Radioactive Tin Beams
in Acta Physica Polonica B
Wen K
(2019)
Dissipation Dynamics of Nuclear Fusion Reactions
in Acta Physica Polonica B
Fujita Y
(2016)
The $T_{z} = \pm 1 \to 0$ and $\pm 2 \to \pm 1$ Mirror Gamow--Teller Transitions in $pf$-shell Nuclei
in Acta Physica Polonica B
Shand C
(2015)
Structure of $^{207}$Pb Populated in $^{208}$Pb + $^{208}$Pb Deep-inelastic Collisions
in Acta Physica Polonica B
Lalkovski S
(2016)
The UK NuStAR Project
in Acta Physica Polonica B
Catford W
(2015)
Structure of $^{26}$Na via a Novel Technique Using ($d,p\gamma $) with a Radioactive $^{25}$Na Beam
in Acta Physica Polonica B
Briz J
(2016)
Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra Determination
in Acta Physica Polonica B
Collins S
(2016)
Half-life determination of the ground state decay of 111 Ag
in Applied Radiation and Isotopes
Collins SM
(2018)
Investigation of ?-? coincidence counting using the National Nuclear Array (NANA) as a primary standard.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Shams H
(2016)
A preliminary evaluation of naturally occurring radioactivity concentration levels across the State of Kuwait.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Collins SM
(2015)
The half-life of ²²7Th by direct and indirect measurements.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Larijani C
(2017)
Reference materials produced for a European metrological research project focussing on measurements of NORM.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Collins SM
(2015)
Precise measurements of the absolute ?-ray emission probabilities of (223)Ra and decay progeny in equilibrium.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Lorusso G
(2016)
Development of the NPL gamma-ray spectrometer NANA for traceable nuclear decay and structure studies.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Collins SM
(2015)
Direct measurement of the half-life of (223)Ra.
in Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
Alazemi N
(2016)
Soil radioactivity levels, radiological maps and risk assessment for the state of Kuwait.
in Chemosphere
Schuetrumpf B
(2018)
The TDHF code Sky3D version 1.1
in Computer Physics Communications
Heine M
(2022)
Direct Measurement of Carbon Fusion at Astrophysical Energies with Gamma-Particle Coincidences
in EPJ Web of Conferences
Stevenson P
(2016)
Resonances and reactions from mean-field dynamics
in EPJ Web of Conferences
Morales A
(2015)
First measurement of the ß -decay half-life of 206 Au
in EPL (Europhysics Letters)
Description | The grant has funded experimental work at RIKEN, TRIUMF, Argonne, GANIL and other international laboratories and theoretical collaborations with RIKEN, MSU, GSI and other major centres. New isomeric states in exotic nuclei were discovered and much-improved measurements of nuclear astrophysical cross sections were determined. |
Exploitation Route | Outputs are published in the leading scientific journals and will feed into improved nuclear astrophysics and nuclear structure theories. |
Sectors | Other |
URL | http://www.nucleartheory.net/NPG/recent_publications.htm |