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
Mahzoon H
(2019)
Nuclear slabs with Green's functions: mean field and short-range correlations
in The European Physical Journal Special Topics
Cáceres L
(2015)
Nuclear structure studies of F 24
in Physical Review C
Doherty D
(2015)
Nuclear transfer reaction measurements at the ESR-for the investigation of the astrophysical 15 O( a , ? ) 19 Ne reaction
in Physica Scripta
Phong V
(2019)
Observation of a µ s isomer in In 85 49 134 : Proton-neutron coupling "southeast" of Sn 82 50 132
in Physical Review C
Sumikama T
(2021)
Observation of new neutron-rich isotopes in the vicinity of Zr 110
in Physical Review C
Orrigo S
(2016)
Observation of the 2 + isomer in Co 52
in Physical Review C
Scott M
(2017)
Observation of the Isovector Giant Monopole Resonance via the Si 28 ( Be 10 , B * 10 [ 1.74 MeV ] ) Reaction at 100 A MeV
in Physical Review Letters
Sword C
(2019)
Observation of three-neutron sequential emission from O * 25
in Physical Review C
Divaratne D
(2018)
One- and two-neutron removal cross sections of O 24
in Physical Review C
Gade A
(2016)
One-neutron pickup into Ca 49 : Bound neutron g 9 / 2 spectroscopic strength at N = 29
in Physical Review C
Kobayashi N
(2016)
One-neutron removal from Ne 29 : Defining the lower limits of the island of inversion
in Physical Review C
Spieker M
(2019)
One-proton and one-neutron knockout reactions from N = Z = 28 Ni 56 to the A = 55 mirror pair Co 55 and Ni 55
in Physical Review C
Rios A
(2017)
Pairing and short-range correlations in nuclear systems
Rios A
(2017)
Pairing and Short-Range Correlations in Nuclear Systems.
in Journal of low temperature physics
Ding D
(2016)
Pairing in high-density neutron matter including short- and long-range correlations
in Physical Review C
Gómez-Ramos M
(2019)
Perey-effect in continuum-discretized coupled-channel description of ( d, p ) reactions
in Journal of Physics G: Nuclear and Particle Physics
Lestinsky M
(2016)
Physics book: CRYRING@ESR
in The European Physical Journal Special Topics
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
Atanasov D
(2015)
Precision Mass Measurements of ^{129-131}Cd and Their Impact on Stellar Nucleosynthesis via the Rapid Neutron Capture Process.
in Physical review letters
Regan P
(2015)
Precision measurement of sub-nanosecond lifetimes of excited nuclear states using fast-timing coincidences with LaBr3(Ce) detectors
in Radiation Physics and Chemistry
Rosenbusch M
(2015)
Probing the N=32 Shell Closure below the Magic Proton Number Z=20: Mass Measurements of the Exotic Isotopes ^{52,53}K.
in Physical review letters
Van Den Bossche R
(2020)
Production of transuranium isotopes in Ne 20 -induced incomplete fusion reactions
in Physical Review C
Larijani C
(2017)
Progress on the chemical separation of fission fragments from 236 Np produced by proton irradiation of natural uranium target
in Radiation Physics and Chemistry
Mohamud H
(2017)
Progress towards the development of a rapid analytical approach for separation of 226 Ra using dibenzo-18-crown-6 ether functionalised silica (SiO 2 ) disks
in Radiation Physics and Chemistry
Larijani C
(2015)
Progress towards the production of the 236gNp standard sources and competing fission fragment production
in Radiation Physics and Chemistry
Paul N
(2019)
Prominence of Pairing in Inclusive (p,2p) and (p,pn) Cross Sections from Neutron-Rich Nuclei.
in Physical review letters
Gerst R
(2020)
Prompt and delayed ? spectroscopy of neutron-rich Kr 94 and observation of a new isomer
in Physical Review C
Walker P
(2020)
Properties of 187Ta revealed through isomeric decay
Walker PM
(2020)
Properties of ^{187}Ta Revealed through Isomeric Decay.
in Physical review letters
Auranen K
(2019)
Proton decay of 108I and its significance for the termination of the astrophysical rp-process
in Physics Letters B
Chen ZQ
(2019)
Proton Shell Evolution below ^{132}Sn: First Measurement of Low-Lying ß-Emitting Isomers in ^{123,125}Ag.
in Physical review letters
Taprogge J
(2016)
Proton-hole and core-excited states in the semi-magic nucleus 131In82
in The European Physical Journal A
Nakhostin M
(2018)
Pulse-height loss in the signal readout circuit of compound semiconductor detectors
in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Morrison L
(2023)
Quadrupole and octupole collectivity in the semi-magic nucleus 80 206 Hg126
in Physics Letters B
Morrison L
(2020)
Quadrupole deformation of Xe 130 measured in a Coulomb-excitation experiment
in Physical Review C
Holl M
(2019)
Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range
in Physics Letters B
Atar L
(2018)
Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength.
in Physical review letters
Chen S
(2019)
Quasifree Neutron Knockout from ^{54}Ca Corroborates Arising N=34 Neutron Magic Number.
in Physical review letters
Reiter M
(2018)
Quenching of the N = 32 neutron shell closure studied via precision mass measurements of neutron-rich vanadium isotopes
in Physical Review C
Lapoux V
(2016)
Radii and Binding Energies in Oxygen Isotopes: A Challenge for Nuclear Forces.
in Physical review letters
Judge S
(2017)
Radionuclide metrology research for nuclear site decommissioning
in Radiation Physics and Chemistry
Fernández-Domínguez B
(2018)
Re-examining the transition into the N = 20 island of inversion: Structure of 30Mg
in Physics Letters B
Fernández-Domínguez B
(2018)
Re-examining the transition into the N=20 island of inversion: structure of $^{30}$Mg
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 |