University of the West of Scotland Nuclear Physics Group Consolidated Grant

Lead Research Organisation: University of the West of Scotland
Department Name: School of Computing

Abstract

Despite more than a century of intense experimental and theoretical research, the nuclear many-body quantum system remains a challenge. In the century that has followed, numerous advances in accelerator and detector technology have firmly established nuclear physics as an international activity at the forefront of scientific research. In the past few decades, the quest to understand the properties of exotic nuclei ever further from the valley of stability has led to considerable experimental progress. The programme of research described in this Consolidated Grant application covers research into the structure and properties of atomic nuclei lying far from stability and collective behaviour in stable nuclei which remains poorly understood.

Recent experimental observations, supported by theoretical calculations, have suggested that the structure of exotic nuclei may be different from those near stability. The well-known sequence of magic numbers, corresponding to energy gaps in nuclear shell structure, is now thought to change in nuclei with an extreme excess of neutrons. The evidence for such a change is already convincing around neutron number N=20, and similar effects are expected for the other shell gaps at N=28, 50, and 82. In order to provide a test of nuclear models, experimental data are needed. In this respect, we will focus on the proton-rich nuclei around Sn100 (N=Z=50).

An important consideration in the description of an atomic nucleus is its shape. It is well established that nuclei with filled shells of neutrons and protons are spherical, and nuclei with partially-filled shells can become deformed. An exotic form of deformation is when the nucleus takes on a reflection-asymmetric "pear" shape. Such octupole deformation is most prominent in localized regions of the nuclear chart, such as the light actinide region (radium, thorium, uranium nuclei with A~224) and lanthanides near barium-144. In our research programme, we will make a comprehensive study of octupole deformation in nuclei, focusing on the actinide and lanthanide regions, as well as the proton-rich nuclei near N=Z=56. Recent developments in accelerator and detector technology will now allow new types of experiments to be performed to provide new insights into this novel type of deformation. In our research programme, we will make a comprehensive study of octupole correlations in nuclei, focusing on the actinide and lanthanide regions, as well as the proton-rich nuclei near N=Z=56. The mirror-symmetry-violating pear shape allows for the search for physics that is responsible for the existent matter-antimatter symmetry violation.

High-powered laser systems are now offering a new method of producing and accelerating particles. Focussing their beams on small areas creates volumes with extreme high energy densities, in which nuclear reactions can happen or from which intense beams of charged particles are emitted. Parts of our research will exploit this novel technical development to explore aspects of nuclear physics which are not possible by conventional means.

Our research will performed using varius different experimental techniques. For example, we will carry out Coulomb-excitation experiments at ISOLDE, electron-gamma coincidence spectroscopy and lifetime measurements at JYFL, and laser-induced nuclear reactions at the new ELI-NP facility in Magurele, Romania. The requested funds will provide support for postdoctoral research associates and PhD students to help carry out this work, as well as funds for travel and subsistence. We have also requested funds to enable world leading theoretical nuclear physicists to visit our group to help with the interpretation of our results, and to provide important theoretical input into our experimental research programme.

Planned Impact

This STFC-funded research will have a considerable impact on society. While some aspects will have an instant impact, and the benefits are immediately obvious, other aspects are more indirect, with the benefits realized in the long term.

A direct impact of the work of the UWS nuclear physics group is in their provision of expertise to the local community. In particular, one member of the group (O'Donnell) has an on-going project working with the West of Scotland PET Centre at NHS Gartnavel Hospital (Glasgow) in which the use of a high-purity germanium detector is being used to quantify and determine the nature of radioactive waste resulting from the production of the PET isotope fluorine-18. This project has already yielded two forms of impact. The first is reduced cost to the NHS, both in the form of zero cost lending of equipment and expertise but also in changes being implemented in the storage and disposal of the radioactivity. The second impact of this project has been in the education of students at undergraduate and postgraduate level.

Another short-term impact is to attract the interest of school children, and hence to increase the numbers of students studying physics at university. The RCUK Review of UK Physics (Wakeham Report, 2008) stated that particle physics, nuclear physics, and astrophysics were the most cited subjects for first-year undergraduate students being attracted physics. Dissemination of results from large-scale nuclear physics projects, such ISOLDE and AGATA, will act as an incentive for students to study physics. The resulting larger numbers of physics students will equip the UK with a larger scientifically-minded workforce, which will have a positive effect on the economy. This impact will be maximized by presenting the results of this STFC-funded research to local schools and to the general public.

Another impact of this research will be in the provision of skills to employees of the nuclear industry and other parts of the nuclear sector. With energy production high on political agendas, and the imminent new-build of nuclear power stations and the ongoing programme of decommissioning, the teaching of nuclear skills is presently in great demand. Our STFC-funded research will enable us to stay at the forefront of technical developments. In turn, we will transfer our knowledge of, for example, radiation detection, to industry. We intend to carry out a programme of nuclear-skills training in several different ways. Firstly, we have an ongoing undergraduate degree programme entitled "Physics with Nuclear Technology", which has a strong bias towards applications of nuclear physics. Similarly, we are presently considering the development of an MSc in Nuclear Science and Technology, which will cover nuclear energy as well as nuclear medicine and imaging, and other areas of nuclear technology. All of our skills training will be aimed at both local (Scottish) and UK students, and also students from abroad. We will thereby contribute to providing the UK with highly-skilled manpower and we will attract inward investment from overseas.

Instrumentation and methods developed in nuclear-physics research have often found applications elsewhere. Nuclear-based techniques have become commonplace in industry, and nuclear medical imaging is now an integral part of the treatment provided by hospitals. Such techniques have clear benefits to society and improve the quality of life. Cancer therapy using beams of gamma rays and charged particles saves thousands of lives each year. These applications use methods and techniques that were developed in fundamental research in previous years and decades. Similarly, our STFC-funded research, proposed here, will lead to applications in the future.

Publications

10 25 50
publication icon
Scheck M (2017) $\beta $ Decay as a New Probe for the Low-energy E1 Strength in Acta Physica Polonica B

publication icon
Barber L (2020) A charge plunger device to measure the lifetimes of excited nuclear states where transitions are dominated by internal conversion in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

publication icon
Mallaburn M (2019) A time-of-flight correction procedure for fast-timing data of recoils with varying implantation positions at a spectrometer focal plane in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

publication icon
Olaizola B (2021) Ba 145 and La 145 , 146 structure from lifetime measurements in Physical Review C

 
Description INFN Legnaro National Laboratory 
Organisation National Institute for Nuclear Physics
Department Legnaro National Laboratories
Country Italy 
Sector Academic/University 
PI Contribution We carry out experiments at the Legnaro National Laboratory, using equipment such as the Galileo gamma-ray spectrometer, the RFD, and Prisma. AGATA will be based at the Legnaro Laboratory, and UWS will play a leading role in the physics of AGATA at Legnaro.
Collaborator Contribution Our partners/collaborators in Italy are instrumental in running the laboratory and the equipment that we exploit.
Impact Publications are given in the relevant lists. This collaboration is not multi-disciplinary.
 
Description JYFL 
Organisation JYFL
PI Contribution Proposal and leadership of experiments and analysis of data. Provision of some experimental equipment.
Collaborator Contribution Proposal and leadership of experiments and analysis of data. Provision of some experimental equipment. Provision of accelerated beams at the JYFL laboratory in Finland.
Impact Multiple outputs from this collaboration. Outputs are given in the list of publications.