University of the West of Scotland Nuclear Physics Group Consolidated Grant

More than a century since Rutherford identified the atomic nucleus in alpha-particle scattering experiments in Manchester, the science of nuclear physics remains vibrant and active. Over the past 100 years, there has been a wealth of experimental and theoretical research that has led to milestone results and discoveries, such as the discovery of the neutron, the development of successful models of the nucleus, and the identification of numerous novel decay modes. Progress in nuclear physics has gone hand-in-hand with the development of particle accelerators, which started with modest electrostatic machines, capable of accelerating light ions, and resulting in modern day accelerators capable of accelerating any nucleus up to uranium-238, with energies of 10 MeV per nucleon or more. Facilities now exist that can accelerate radioactive ions, and there is effort being put into improving the intensities, energies, and purity of radioactive beams. Despite the wealth of research activity in nuclear physics, and the maturity of the subject, a complete understanding of the atomic nucleus has still not been achieved. There are still many open questions that need to be answered, which we will address is our research programme. Also, technological and scientific developments in nuclear physics are leading to applications outside of the areas of fundamental science - nuclear-related concepts are now used in many areas of industry and medicine, leading to additional areas of research. Our programme of research in this Consolidated Grant application covers research into the structure, behaviour and properties of atomic nuclei that lie far from stability as well as collective behaviour in stable nuclei, which remains poorly understood.

One of the main parts of our programme of research is the study of the shapes of atomic nuclei. It is well established that nuclei with filled shells of neutrons and protons are spherical, and nuclei with partially-filled shells can become deformed. One of the themes within our research programme will study quadrupole shaped nuclei, where the nucleus takes on a rugby-ball shape. This type of nuclear deformation is prevalent and occurs in many different regions of the nuclear chart. A more 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. Interestingly, atoms containing pear-shaped nuclei are excellent candidates in which to search for matter-antimatter symmetry violating physics.

Over the past 20 years, 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 that lie far from stability. In our programme, we will study the shell structure in a range of nuclei across the nuclear chart, including the nuclei close to the doubly-magic nuclei Sn-100 and Pb-208. Another aspect of our research programme is a study of high-energy collective modes in nuclei, in novel experiments induced by beams of gamma rays. In addition, a new aspect to our research is a study of reactions relevant to nuclear astrophysics, which will include a focus on hydrogen burning that occurs in stars.

One of the main areas of impact of this research is in the provision of skills to employees and future employees of the nuclear-power industry. With ever increasing concern about climate change and our own developing consciousness about our carbon footprints, the provision of nuclear energy remains topical and important. The new-build of nuclear power stations and the ongoing vast programme of decommissioning, means that the teaching of nuclear skills is very important, and is likely to remain important well into the future. Our STFC-funded research will enable us to stay at the forefront of detector and technical developments, which are important to this field. We will transfer knowledge gained in our research to industry, for example, in the use of novel radiation detectors and digital signal processing. We will provide specific skills training and thereby contribute to providing the UK with a highly-skilled workforce who can help to meet future energy demands, and contribute towards the UK industrial strategy.

Another important impact of our research is to attract the interest of school children, and hence to increase the numbers of students studying physics at university. It has previously been reported that "big science", including nuclear physics, particle physics, and astrophysics, is a huge attraction to draw students into physics degrees. Publicizing our results from projects, such as AGATA and ISOLDE at CERN, will act as a carrot-on-a-stick to bring students into university to study physics. A larger number of physics students will equip the UK with a larger numerate and scientifically-minded workforce, which in turn will have a positive effect on the economy. This impact will be maximized by presenting the results of our STFC-funded research to local schools and to the general public; we have requested some modest funds for this purpose.

Our research has a direct impact on the area of nuclear medicine, which can be illustrated with an example: we have an ongoing project working with the West of Scotland PET Centre at Gartnaval Hospital in the West-End of Glasgow, in which we help to identify and quantify radioactive waste that results from the production of the PET isotope fluorine-18. An impact of that project is a better categorization of waste ensuring that low-level waste is separated from high-level waste, therefore providing a cost saving to the NHS. It should also be noted that there are also more indirect impacts of our research in medicine. A good example is our proposed study of the odd-mass actinide nuclei, where we will search for parity doublets that are characteristic of reflection-asymmetric octupole deformation. One of the nuclei we will study is radium-223. However, radium-223 is also now used as a radiopharmaceutical to treat cancers in bone. The radium atoms mimic calcium atoms, and the alpha particles emitted have short range so only do damage to cells in a very localized, targeted area. It is therefore very important that we fully understand the alpha decay of radium-223 and its daughters - which will be studied in our programme.

Additionally, our research studying high-energy beta decays will help to understand additional heat production in operational nuclear reactors, and will have an important influence on the design of future compact reactors.

Nuclear-based techniques have become quite common 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 fundamental STFC-funded research, proposed here, will lead to the medical and industrial applications of the future.