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
Kovoor J
(2023)
Structure studies of Be 13 from the Be 12 ( d , p ) reaction in inverse kinematics on a solid deuteron target
in Physical Review C
Thisse D
(2023)
Study of $$N=50$$ gap evolution around $$Z=32$$: new structure information for $${}^{82}$$Ge
in The European Physical Journal A
Tu X
(2015)
Study of projectile fragmentation reaction with isochronous mass spectrometry
in Physica Scripta
Thies R
(2016)
Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes
in Physical Review C
Wu X
(2017)
Systematic study of multi-quasiparticle K -isomeric bands in tungsten isotopes by the extended projected shell model
in Physical Review C
Tostevin J
(2014)
Systematics of intermediate-energy single-nucleon removal cross sections
Tostevin J
(2014)
Systematics of intermediate-energy single-nucleon removal cross sections
in Physical Review C
Molina F
(2015)
T z = - 1 ? 0 ß decays of Ni 54 , Fe 50 , Cr 46 , and Ti 42 and comparison with mirror ( He 3 , t ) measurements
in Physical Review C
Jolie J
(2015)
Test of the SO(6) selection rule in 196Pt using cold-neutron capture
in Nuclear Physics A
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
Koseoglou P
(2018)
The boundary of the N=90 shape phase transition: $^{148}$Ce
Koseoglou P
(2018)
The boundary of the N=90 shape phase transition: 148 Ce
in Journal of Physics: Conference Series
Mistry A
(2022)
The DESPEC setup for GSI and FAIR
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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
Assié M
(2021)
The MUGAST-AGATA-VAMOS campaign : set-up and performance
Assié M
(2021)
The MUGAST-AGATA-VAMOS campaign: Set-up and performances
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Bocchi G
(2016)
The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus 133 Sb
in Physics Letters B
Bucurescu D
(2016)
The ROSPHERE ?-ray spectroscopy array
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Schuetrumpf B
(2018)
The TDHF code Sky3D version 1.1
in Computer Physics Communications
Lalkovski S
(2016)
The UK NuStAR Project
in Acta Physica Polonica B
Dinmore M
(2021)
Three-body optical potentials in ( d , p ) reactions and their influence on indirect study of stellar nucleosynthesis
in Physical Review C
Timofeyuk N
(2019)
Three-body problem with velocity-dependent optical potentials: a case of ( d , p ) reactions
in Journal of Physics G: Nuclear and Particle Physics
Timofeyuk N
(2018)
Three-nucleon force contribution in the distorted-wave theory of ( d , p ) reactions
in Physical Review C
Timofeyuk N
(2020)
Three-nucleon force contribution to the deuteron channel in ( d , p ) reactions
in Physical Review C
Wood R
(2017)
Three-quasiparticle isomer in Ta 173 and the excitation energy dependence of K -forbidden transition rates
in Physical Review C
Guadilla V
(2019)
Total absorption ? -ray spectroscopy of niobium isomers
in Physical Review C
Guadilla V
(2019)
Total absorption ? -ray spectroscopy of the ß -delayed neutron emitters I 137 and Rb 95
in Physical Review C
Briz J
(2016)
Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra Determination
in Acta Physica Polonica B
Zakari-Issoufou AA
(2015)
Total Absorption Spectroscopy Study of (92)Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape.
in Physical review letters
Moschini L
(2021)
Tracing the dynamical interplay of low-energy reaction processes of exotic nuclei using a two-center molecular continuum
in Physics Letters B
Gamba E
(2019)
Treatment of background in ? - ? fast-timing measurements
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Butler P
(2016)
TSR: A storage and cooling ring for HIE-ISOLDE
in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Wen K
(2018)
Two-body dissipation effect in nuclear fusion reactions
in Physical Review C
Longfellow B
(2020)
Two-neutron knockout as a probe of the composition of states in Mg 22 , Al 23 , and Si 24
in Physical Review C
Goigoux T
(2016)
Two-Proton Radioactivity of ^{67}Kr.
in Physical review letters
Crawford H
(2017)
Unexpected distribution of ? 1 f 7 / 2 strength in Ca 49
in Physical Review C
Estienne M
(2019)
Updated Summation Model: An Improved Agreement with the Daya Bay Antineutrino Fluxes.
in Physical review letters
Hooker J
(2022)
Use of Bayesian Optimization to understand the structure of nuclei
in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Timofeyuk N
(2015)
Widths of low-lying nucleon resonances in light nuclei in the source-term approach
in Physical Review C
Caballero-Folch R
(2017)
ß -decay half-lives and ß -delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N = 126
in Physical Review C
Taprogge J
(2015)
ß decay of Cd 129 and excited states in In 129
in Physical Review C
Jungclaus A
(2016)
ß decay of semi-magic Cd 130 : Revision and extension of the level scheme of In 130
in Physical Review C
Orrigo S
(2016)
ß decay of the exotic T z = - 2 nuclei Fe 48 , Ni 52 , and Zn 56
in Physical Review C
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 |