A Review of UK Nuclear Physics Research - Institute of Physics

An Institute of Physics Report | October 2012

A Review of UK Nuclear Physics Research

Cover image: Strong nuclear force. Conceptual image showing the strong nuclear force (blue) holding together particles such as protons and neutrons in the nucleus of an atom. The strong nuclear force is one of the four fundamental forces underpinning the structure of the universe. Without the strong nuclear force, it would not be possible for atomic nuclei to form. Science Photo Library

Contents Executive summary

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1. INTRODUCTION

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2. The science

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2.1. Hadron physics 2.2. Nuclear matter 2.3. Nuclear structure 2.4. Nuclear astrophysics 2.5. Applied nuclear physics and instrumentation 2.6. The scientific challenges 2.7. Meeting the challenges: an overview

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3. The health of UK nuclear physics

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3.1. Size of the UK nuclear physics community relative to other areas 3.2. The scope of the community 3.3. The research output of the community 3.4. Funding 3.5. Education, training and inspiration 3.6. Summary

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4. Conclusions and recommendations

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4.1. Forming a Centre of Excellence 4.2. Raising the profile of nuclear physics research and applications 4.3. Additional theory group 4.4. Facilities 4.5. Recommendations from the 2009 EPSRC/STFC review

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5. Summary of recommendations

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6. References

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7. Appendix 1: Membership of the panel

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8. Appendix 2: Glossary

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9. Appendix 3: Nuclear physics PhD skills set

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U K N u c l e ar P h y s i c s R e s e ar c h O c t o b e r 2 0 1 2

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Executive Summary This review of the health of UK academic nuclear physics was commissioned by the Science Board of the Institute of Physics (IOP). It is intended to be the first in a series of such reviews of fields within physics aimed at informing IOP policy in the run up to the next government Comprehensive Spending Review. The review looks at contemporary nuclear physics: the questions it addresses, the facilities needed to answer them and the applications of the science. It examines the size of the UK nuclear physics community, how it is funded, the balance between subfields and the division of effort between theory and experiment, and makes a comparison of the UK’s research with that of other leading countries. It surveys the evidence for the health of the subject in the UK in terms of the volume and quality of publications. The training of skilled people at MSc and PhD level is considered, as well as the place of nuclear physics in attracting young people into studying the physical sciences. The review concludes that, worldwide, research in nuclear physics is dynamic and evolving rapidly. Although the UK cannot lead the world in every aspect of nuclear physics, for its research groups to be competitive globally, the UK must have a community of sufficient size and strength to exploit the basic science to take the advantage in developing new technologies and to train the cadre of scientists needed by the UK in areas such as healthcare, the nuclear industry, defence and national security. The review finds that current funding of nuclear physics in the UK is insufficient to maintain excellence in basic nuclear physics, allow the subject to diversify, improve the capability in terms of theory and play a full role in applications. Despite this the research output of the UK nuclear physics community is healthy both in terms of the volume of papers published per academic and in the quality of its publications in comparison with leading international competitors and with other areas of physics in the UK. However, the volume and quality of UK nuclear physics output and the ability of the community to develop new applications and train people in the necessary skills are compromised not only by the lack of investment but by a series of other issues, detailed in the report. The review recommends the following measures to address these issues.

• The Science and Technology Facilities Council (STFC) should take steps to ensure

that UK nuclear physics is funded sufficiently well to maintain scientific excellence, diversify, improve capability in terms of theory, play a full role in applications and train the people required by the UK.

• All UK academic nuclear physics groups should join forces to form a UK Centre of

Excellence (COE) in nuclear physics, which should: – Oversee initial and formal aspects of PhD education and training carried out on a UK-wide basis.

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– Ensure that publicity and communications about nuclear physics are effective, and along with all component UK groups in nuclear physics be proactive in publicising nuclear physics. – Act as a “one-stop” shop to provide a focal point for interaction with potential users of the skills of the nuclear physics community. – Play an active role, in partnership with the STFC and the Engineering and Physical Sciences Research Council, in ensuring that the recommendations of their 2009 Review of Nuclear Science and Engineering, particularly recommendations 6–10 of its report, are implemented.

• The STFC and Research Councils UK should take the initiative to create a new theory

group at an institution other than Surrey or Manchester, with the location of the new group being determined by competition, and supported by the STFC and by matching funds from the successful institution.

• The STFC should negotiate formal association with GSI’s Facility for Antiproton and

Ion Research in Germany and ensure that the UK is in a position to join the European Isotope Separation On-Line project if it gains funding.

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Introduction In preparation for the next government Comprehensive Spending Review (CSR), the Institute of Physics (IOP) has decided to carry out a series of reviews into the health of the major branches of physics. Such reviews would then underpin IOP policy and advice in the run up to the CSR. It was decided by the Science Board of IOP that the first of these reviews would cover nuclear physics. The overall terms of reference for the review were: ●● To review the support for and progress of UK nuclear physics since the 2005 International Review of UK Physics and Astronomy research, in an international context. ●● To assess UK nuclear physics in light of the scope of Research Councils UK (RCUK) and industrially funded activity. ●● To recommend a broad strategy for UK nuclear physics for the next 10 years, including key physics-based challenges, balance between activities, access to facilities, and interdisciplinary and international collaborations.

that the broadest definition, namely the study or application of any branch of nuclear science, was not appropriate and that the review should consider the science and its application by the UK academic community involved in research on the fundamental properties of atomic nuclei. Currently, in the arrangements set up to fund academic research in the UK, this community is largely funded by the STFC. In addition, given the many recent reviews of the subject worldwide and the carefully considered report on the science carried out by the NPAP, it was not sensible to attempt to suggest a radically different approach to a future UK research programme given the worldwide efforts devoted to identifying the most important challenges in nuclear physics. Instead the panel limited itself to comments on aspects of the UK programme. In order to answer the first major question posed in its remit, namely the current state of health of nuclear physics research in the UK, the panel began its work by assembling as much evidence and information as possible. Members of the panel made a series of visits throughout the UK at which The membership of the panel set up to carry out all of the existing research groups were represented, the review is given in Appendix 1. to hear their views on the strengths and weaknesses This report is not written in a vacuum, and many of the field in the UK and the ways in which it is relevant reports are available in the literature, funded. The panel issued a series of separate particularly with regard to the science and the questionnaires to practitioners in the UK and abroad facilities needed to meet the challenges of the and members of the IOP Nuclear Industry group. field. Recent reports include one on the long-range IOP has also issued a series of reports [6–8] on the plan for nuclear physics from the Nuclear Physics size and make-up of the physics community in UK European Collaboration Committee (NuPECC) [1], universities, and the funding of physics research the report of the Nuclear Physics Advisory Panel that is highly relevant for comparison purposes. All (NPAP) [2] and the report of the joint Engineering of this evidence is reviewed in the current report and and Physical Sciences Research Council (EPSRC) conclusions are drawn about the current health of and Science and Technology Facilities Council the field in the UK. (STFC) Review of Nuclear Physics and Nuclear Section 2 of this report outlines the Engineering [3] chaired by Dame Sue Ion, all of contemporary science of nuclear physics, the which are highly relevant to the current report. At the fundamental questions it asks about the universe time of writing this report, two other relevant reports and the diverse range of facilities that it requires became available: the US decadal review of nuclear to answer them. Section 3 brings together the physics from the National Academy of Science [4] available evidence to determine how nuclear and a report by the Birmingham Policy Commission physics has fared since the last international review on The Future of Nuclear Energy in the UK [5]. of UK physics and astronomy. This is followed in At an early stage the panel considered the section 4 by an outline of the panel’s conclusions question of what constitutes nuclear physics and recommendations. Section 5 summarises the in relation to the remit of this review. It decided recommendations.

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The science Modern nuclear physics research, a century on from Ernest Rutherford’s famous alpha scattering experiment, is as vibrant and exciting as ever. As an academic discipline it sits, in terms of length and energy scales, between atomic physics and high-energy particle physics, and not surprisingly therefore overlaps with both of these neighbouring fields. Modern nuclear physics is of course about far more than understanding the structure of nuclei and how their constituent protons and neutrons arrange themselves subject to the rules of quantum mechanics. It addresses fundamental issues relating to how matter was created within the first few microseconds of the Big Bang and how the elements continue to be synthesised in stellar and other astrophysical processes today. Nuclear physicists address a range of fundamental questions – the nature of the strong nuclear force, the way quarks and gluons interact within nuclear matter, the origins of mass and spin in protons and neutrons, and the extreme limits of nuclear stability – while the applications of nuclear science

range from medicine to nuclear power and waste management to materials science. This section outlines the different areas of modern nuclear physics research, along with some of the recent highlights of the research carried out by UK nuclear physicists. The section ends with some of the large remaining challenges in the field. Nuclear physics research in the 21st century can be loosely divided into six areas1, within each of which the UK academic community is currently actively working: ●● Hadron physics ●● Nuclear matter ●● Nuclear structure ●● Nuclear astrophysics ●● Applied nuclear physics and instrumentation

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The sixth area (fundamental symmetries and neutrino physics) is omitted because it is funded in the UK under the heading of particle physics rather than nuclear physics.

2.1. Hadron physics Hadrons are strongly interacting composite particles consisting of “current quarks” and the strong nuclear force carriers, gluons. These constituents cannot exist in isolation and are

Figure 1: Different electron energies probe different aspects of nuclear and nucleon structure because the wavelength shortens with energy and allows properties on different length scales to be examined Nucleus e

e–

E0 ≈ 100 MeV e

e–

E0 ≈ 1 GeV e

fm–1

q = 0.5 Δr = 2 fm

e–

E0 ≈ 1 GeV Quark e

q = 5 fm–1 Δr = 0.2 fm

e–

E0 ≈ 200 GeV

q = 5 fm–1 Δr = 0.2 fm q = 50 fm–1 Δr = 0.02 fm

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instead always confined inside hadrons in various “colour neutral” combinations. There are two classes of hadrons: baryons (such as protons and neutrons), which contain three constituent quarks; and mesons (such as the pion), which consist of quark–anti-quark pairs. Indeed, pions are responsible for carrying the long-range part of the strong nuclear force that binds the protons and neutrons (nucleons) inside nuclei. The mass of the constituent quarks in nucleons makes up only approximately 1% of the nucleon mass, and a key issue in nuclear physics is to understand how the remainder of this mass comes about from the binding energy that keeps the quarks confined. Similarly, the spin of the nucleon cannot be understood in terms of the spins of the constituent quarks. The theory of the strong nuclear force, quantum chromodynamics (QCD), describes the way quarks interact via the exchange of gluons. How this underlying theory is linked to the observed properties of the nucleons in nuclei is one of the major challenges being addressed in nuclear physics today. A key difference between the strong nuclear force and the more familiar forces of gravity and electromagnetism is that, unlike

Figure 2: The phases of nuclear matter and the regions of the phase diagram to be probed by ALICE at the Large Hadron Collider (LHC), the Relativistic Heavy Ion Collider (RHIC) at Brookhaven, USA, and the Compressed Baryonic Matter experiment at GSI’s Facility for Antiproton and Ion Research (FAIR)

Image courtesy of NuPECC Long Range Plan 2010: Perspectives of Nuclear Physics in Europe, December 2010

Study of exotic nuclei using knockout studies The efforts of nuclear theorists in the UK have played a major role in elucidating and interpreting the results of some of the most exciting experimental work of the last 10–15 years: the use of knockout reactions as a probe of exotic neutron-rich and proton-rich nuclei. These experiments have been used to determine in detail the structure of light nuclei, particularly those at the limits of stability in which the valence particles are very weakly bound. The momentum distribution of the knocked-out nucleon cluster of nucleons reveals its orbital angular momentum and excitation spectrum. A key contribution to this has been the UK-led effort to develop a theoretical reaction framework in which the experimental results can be understood. UK experimentalists have also been at the forefront of important measurements to determine evolving singleparticle structures in light nuclei; for example, the d-wave contribution to the ground state of 12 Be and single-particle levels in neon isotopes. These measurements have been performed at the GANIL accelerator in France, and will be a strong

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k2

k1 KA

KC

A A−2

kC

Schematic of a knockout reaction whereby two (red) nucleons in the projectile (left) are knocked out in a collision with a target (right). Source Phys. Rev. Lett. 2009 102 132502.

component of the programme at R3B at the GSI in Germany, where the structure of dripline oxygen and fluorine nuclei will be studied.

•Mechanisms in Knockout Reactions Phys. Rev.

Lett. 2009 102 232501 •Two-Nucleon Knockout Spectroscopy at the Limits of Nuclear Stability 2009 Phys. Rev. Lett. 102 132502

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them, the strong nuclear force between two quarks becomes stronger the further they are apart, leading to confinement and giving rise to complex phenomena that need to be understood in order to fully comprehend the structure of nuclei starting from QCD. One model that attempts to describe this is the flux tube model, in which strings of “glue” are formed between quarks through gluon–gluon interaction. If these “flux tubes” could be excited, it should be possible to create so-called hybrid mesons, which could be identified by their unusual combinations of quantum numbers. The aim is to achieve a clear map of the internal structure of nucleons. These questions are being addressed by experiments involving UK nuclear physicists working at international facilities, including the Mainz Microtron, ELSA (Bonn) and DESY (Hamburg) in Germany, COMPASS at CERN in Switzerland and the Jefferson Laboratory (JLab) in the USA. UK physicists are highly active in a number of these experiments, particularly at the Mainz Microtron and JLab. 2.2. Nuclear matter At extreme conditions of high temperature and pressure, protons and neutrons no longer behave as independent entities and instead melt away, releasing their bound quarks and gluons to form a new phase of nuclear matter called the quark– gluon plasma (QGP). This new phase of matter can be created in high-energy nuclear collisions, and understanding its properties and the phase transition between this QGP and normal nuclear matter in which the quarks and gluons are confined within hadrons are among the central questions being addressed by nuclear physicists. Details of the phase diagram of nuclear matter can be understood only by improving the understanding of the strong nuclear force itself. Progress has been made over the past few decades, but there is still a long way to go. Experiments at the Relativistic Heavy Ion Collider (RHIC) in the USA and ALICE at CERN aim to elucidate the different phases of the unconfined nuclear matter with properties ranging from a near-perfect fluid of strongly interacting quarks and gluons to a gas of weakly interacting particles. Addressing nuclear matter at these extremes will help us to understand the nature of the strong nuclear force as it acts within normal nuclear matter in nuclei and to test the predictions of QCD. Future projects include the proposed Compressed Baryonic Matter experiment at GSI’s Facility for

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2 Nuclear molecules

The formation of a nuclear molecule. A neutron at each red alpha particle lies in a p-orbital. Linear combinations of p-orbitals give rise to molecular orbits for the valence neutrons.

The way that protons and neutrons can arrange themselves within light nuclei can be quite varied; for example, it is known that the four protons and four neutrons in 8Be cluster into two groups forming two distinct alpha particles. The UK has made an important contribution to understanding the cluster structure of such light systems. Recently, in an experiment led by the UK, it has been shown that when two neutrons are added to this two-alpha-particle cluster to form the nucleus 10 Be, the neutrons are covalently exchanged between the two alpha particles just as electrons are exchanged between atoms in covalent atomic molecules. These nuclear systems have been called nuclear molecules. The experimental group is currently attempting to form nuclear systems formed from three alpha particles bound by covalent neutrons – what might be referred to as nuclear polymers.

•Phys. Rev. Lett. 2006 96 042501 Antiproton and Ion Research (FAIR) in Germany, which aims to explore the QCD phase diagram at even higher matter densities. 2.3. Nuclear structure Atomic nuclei provide a unique laboratory for testing quantum many-body effects and correlations that take us beyond a “mean field” description of nuclei as bags of nucleons, each of which feels the average potential of all of the others. It is here that nuclear physics connects with another of the main themes of the physical sciences, which is concerned with understanding composite systems of bound, interacting objects. A 9

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Figure 3: An 45Fe ion enters an optical time projection chamber from the left, stops in the gas and emits two protons, seen as a V shape. Source Nature Physics 2007 3 836–837

Reprinted with permission from Macmillan Publishers Ltd: Nature Physics 2007 3 836–837 and M Pfutzner

major effort is being made to build models of nuclei from first principles. Such ab initio calculations face significant and challenging hurdles requiring large-scale computational power, but the ultimate aim is to understand the structure of all nuclei starting from this bottom-up approach. The problem is that there is currently no single theory of nuclear structure that describes all nuclei, so a suite of approaches and models are usually applied depending on which region of the nuclear landscape is being investigated. Thus, many of the observable properties of light nuclei can be reproduced using few-body and cluster models, while the nuclear shell model is a reliable theory for medium-mass nuclei. For heavy nuclei, meanfield approaches based on collective properties of many nucleons are appropriate – and it has indeed been found that out of such complex many-body interactions arise some fairly simple structures.

Cosmic gamma-ray emission

A gamma-ray view of the sky taken by the COMPTEL instrument aboard NASA’s Compton Gamma Ray Observatory. The sky is projected onto the Milky Way. In this projection the plane of the galaxy runs across the middle of the picture. Image courtesy of NASA.

The observation of characteristic 1.809 MeV gamma rays from the interstellar medium associated with the decay of 26Al was one of the most important discoveries in the history of gamma-ray astronomy. This provided the most convincing evidence of ongoing nucleosynthesis in our galaxy. Since that discovery, nuclear astrophysicists have attempted to ascertain the stellar origin of 26Al, with considerable interest in determining the rates of the nuclear processes associated with its creation and destruction. Recent satellite missions have indicated that

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massive Wolf–Rayet stars are the likely dominant astrophysical source of 26Al and that in such environments the 26Al(p,gamma)27Si reaction is responsible for its destruction. The rate of this reaction in Wolf–Rayet stars has, until recently, remained largely uncertain. In an experimental study led by UK researchers, precise energies and spin assignments of key resonant states have been obtained for the reaction, reducing uncertainties in the rate by a factor of 100,000.

•Phys. Rev. Lett. 2009 102 162502

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2 The nuclear magic of tin

The array of germanium detectors at the heart of the experiment on the beta decay of 100Sn. The tin (Sn) ions identified by the GSI’s Fragment Recoil Separator enter from the right and are implanted in an array of double-sided silicon strip detectors, surrounded by the germanium gamma ray. Image courtesy of P Regan.

Magic numbers are key benchmarks that define the nuclear landscape. It is thought that far from stability these closed shell structures may dissolve owing to changes in the ordering of nuclear single-particle orbits. However, experiments performed in international collaborations, with UK scientists playing leading roles, have shown that in the region of doubly magic tin-100 (100Sn) – the heaviest doubly magic nucleus with equal proton and neutron numbers – the opposite is true, with the first observation of a single-particle excited state relative to the 100Sn core. Evidence has also been found for enhanced super-allowed beta decays across the N = Z = 50 shell closures, confirming the robust nature of this double shell closure. Detailed high-precision studies of the Explaining the rich variety of structures of nuclei in a more universal way remains a key issue on which progress is being made; for example, using energy density functional theory. The limits of nuclear stability can be explored in a variety of ways, ranging from the study of excitations of individual nucleons within nuclei to their collective behaviour, such as nuclear vibrations and deformations. Approximately 7500 nuclear species (combinations of protons and neutrons) may exist as a bound state, but only a quarter have so far been identified, and fewer have been studied properly. However, synthesising and studying new

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beta decay of 100Sn itself are consistent with a very pure, simple proton-to-neutron spin-flip transition that reveals the fastest Gamow–Teller decay rate of any nucleus yet studied. Such information is critical to understanding the average potential experienced by the protons and neutrons within the nuclear medium and how beta decay strength is quenched in nuclei relative to free neutron decay. The UK-led experiments have been performed using a variety of techniques at three national accelerator laboratories in the USA and Germany.

•Nature 2012 486 341 •Phys. Rev. Lett. 2007 99 022504 •Nature 2007 449 411 nuclides is important not merely because these are uncharted territories of the nuclear landscape. They exhibit new and surprisingly different features and properties that challenge the understanding of the rules governing nuclear structure. Already, isotopes of light elements with weak binding or unusual matter and charge distributions have led to exciting new physics. For example, recent studies have shown that the magic numbers, previously thought to be the immutable, most stable configurations of nucleons in quantum mechanical terms, change radically further away from stability. In addition, having access to, and an understanding of, a 11

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wide region of the nuclear landscape provides an expanded “gene pool” of nuclides from which those that isolate or amplify key aspects of physics can be selected. A recent challenge in nuclear physics is to identify and study nuclei far from stability – that is, nuclei with proton-to-neutron ratios (related to the concept of isospin) that differ dramatically from those of the nuclides making up the atoms of normal stable matter. Understanding the forces in nuclei far from stability is one of the challenges in the study of nuclear structure today. Beyond the basic interest in the evolution of nuclear structure from near to far from stability, this evolution is crucial to the synthesis of the heavy elements in the universe, discussed in more detail in section 2.4. Already, a number of such exotic species have been produced at radioactive beam facilities around the world, and new phenomena such as neutron skins and halos, exotic alpha-particle clustering and alterations to the traditional picture of nuclear shell structure have been discovered. Nuclei display a wealth of collective phenomena in which correlated nucleon motions lead to a variety of nuclear shapes, to excitation modes that can be viewed in terms of oscillations and rotations of those shapes, and to often rapid evolution of structure with neutron and proton number. Techniques to study these facets of nuclei, and the nucleon interactions responsible for them, have

advanced considerably in recent years and are now being applied to the study of exotic nuclei, in which new phenomena are expected. One of the many active areas of nuclear research is the synthesis of the very heaviest elements that can exist. Such super-heavy nuclei are highly unstable because the range of the strong nuclear force is too short to hold together all of the nucleons against the longer-ranged Coulomb repulsion of the protons. Nevertheless, theory predicts that at a certain mass, around Z = 124, nuclei may be stable again because of emerging additional binding from the shell structure produced by their nucleons. Careful and ingenious spectroscopic studies have recently been carried out by UK experimentalists to attempt to understand the way that the protons and neutrons arrange themselves in their shell structure in super-heavy elements such as nobelium (Z = 102). Such understanding will guide efforts to generate nuclei at the centre of the stability island of super-heavy nuclei. 2.4. Nuclear astrophysics It is no exaggeration to say that nuclear processes have shaped our universe from the first few seconds after the Big Bang to the evolution of galaxies and stars, including the processes that drive the Sun and sustain life on Earth. It is through a growing understanding of what goes on inside atomic nuclei that it is now possible to

Figure 4: A map of the nuclear landscape showing the regions where an understanding of nuclear processes feeds into that of a variety of astrophysical processes Red Giant Stars p-process

s-process

50 X-ray bursts

αp-process novae

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20 40 20 10

Z N

12

90

30

hot CNO cycle 10

110

r-process

rp-process 40

50

70

100

80

Supernovae

30 stable nuclide drip line

Inhomogeneous Big Bang

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2 Figure 5: Schematic diagram of the interior of a neutron star colour - superconducting strange quark matter

surface • hydrogen/helium plasma • iron nuclei outer crust

• atomic nuclei • electron gas

inner crust • heavy atomic nuclei • relativistic electron gas • superfluid neutrons outer core • neutrons, superconducting protons • electrons, muons

radius ∼10 to 14 km, mass ∼1 to 2 Msun

explain how all of the elements in the universe are synthesised, including the atoms that make up our bodies. To map out this picture on the very largest scale, nuclear physicists work with astronomers, astrophysicists and cosmologists in close and fruitful collaborations. Current areas of research include the study of the fate of stars, particularly such dramatic events as supernova explosions. Understanding these violent processes via complex simulations requires input from nuclear physics to map the nuclear reactions that take place. This is the stage in a star’s evolution when many of the elements on Earth will have been created. Likewise, one outstanding challenge is to develop a reliable and consistent equation of state that must be constrained by experimental data from nuclear physics experiments. Nuclear matter studies also feed into the understanding of the nature and structure of neutron stars left behind after supernova explosions. Studies into lower-energy nuclear reactions provide useful information about the evolution of massive stars and the amounts of energy released in stellar processes, as well as the relative abundance of the isotopes of elements, such as carbon and oxygen, that are vital for life on Earth.

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inner core • neutrons, protons, electrons, muons • hyperons (Σ, Λ, Ξ) • boson (π, K) condensates • deconfined (u,d,s) quarks/colour - superconducting quark matter

Here, careful measurements are being made and reliable theoretical models developed of the key nuclear reactions involved. 2.5. Applied nuclear physics and instrumentation Advances in instrumentation and detectors play a vital role in nuclear physics, from novel radioactive and cryogenic targets to sophisticated particle and gamma-ray detectors. New methods of accelerating nuclear particles are also being developed and can then be applied in other fields, such as lasers to accelerate ion beams for cancer treatment and the creation of a compact source of muons for use in security and waste management. The following examples illustrate the applications of the science carried out by UK nuclear physicists. The Advanced Gamma Tracking Array (AGATA) [9], which represents a breakthrough in the way that gamma-ray spectroscopy is carried out, will have a wide range of uses in nuclear physics. It will shed light on how elements are synthesised in stars and may even aid the discovery of new superheavy elements by allowing us to understand their underlying shell structure. The basic technology of the array will also bring developments in medical imaging and diagnostic machines that produce

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2 The 3D structure of the nucleon The framework of generalised parton distributions (GPDs) will enable the formation of a threedimensional picture of quark distributions inside the nucleon. It also allows access to the orbital angular momentum of quarks. Over the last few years, the HERMES (DESY, Germany) and CEBAF Large Acceptance Spectrometer (JLab, USA) collaborations have made significant advances towards the extraction of GPDs through pioneering measurements of asymmetries in deeply virtual compton scattering. The UK-led final upgrade of the HERMES experiment with a recoil detector was the most recent step in this development. Measurements at JLab and the Mainz Microtron in Germany also feed into the GPD framework. GPD physics is at the very core of the physics programme for the upcoming JLab energy upgrade, and the expertise amassed through HERMES and the Large Acceptance Spectrometer will enable the UK to take a leading role in this work.

Visualisation of a proton showing gluon fields and an electron scattering from a quark. Image courtesy of D Leinweber

•Over the last four years, 22 Phys. Rev. Lett. articles have been published in this field

alternative detector materials based on cadmium, zinc and tellurium work at room temperature. This technology is being developed in mobile X-ray and gamma-ray cameras for analytical, medical and space-science applications. Neutrons emitted from nuclear reactions are more difficult to detect because they do not respond to electric fields. New detectors are being developed for astrophysics experiments that combine a liquid scintillator with digital pulse-shape technology and could be used for radiation monitoring in nuclear power stations. Another application is scintillating fibre technology, developed for nuclear physics research, to track cosmic muons as they pass through concrete barrels. This muon tomography offers a means of inspecting radioactive waste drums to determine any unwanted uranium in the concrete matrix. Such diagnostics are a key part of the suite of tools necessary to handle radioactive waste safely and efficiently. Image courtesy of NuPECC Long Range Plan 2010: The Scottish Centre for the Application of Perspectives of Nuclear Physics in Europe, December 2010 Plasma-based Accelerators [10] is a new initiative three-dimensional images of people’s bodies, to develop laser–plasma accelerators based on providing information about the functioning of the Wakefield principle. Building on a collaboration internal organs and detecting disease and tumours. between nuclear physicists and plasma physicists, The same technology is also being developed for these new accelerators will potentially lead to use in national security. devices that can accelerate a range of particle and Germanium detector arrays, such as AGATA, must ion species in “table-top” distances. The initiative be cooled to liquid-nitrogen temperatures, but will include a programme to investigate the possible

Figure 6: A section of the Advanced Gamma Tracking Array comprising 45 segmented germanium crystals

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2 Radioactive decay heat 0.8

EEM ENDF/B-VII EEM ENDF/B-VII+TAGS tobias compilation

fγ(t) x t (MeV/fission)

0.7 0.6 0.5 0.4 0.3 0.2 1

10

102 cooling time (s)

103

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Comparison of the calculated electromagnetic decay heat component for 239Pu with the data regarded as the standard (Tobias, CEGB Report No. RD/B/6210/R89, 1989) before and after the inclusion of the new measurements. Phys. Rev. Lett. 2010 105 202501

During operation, approximately 8% of the power of a fission reactor originates from the heat generated by the radioactive decays of the fission products. When the reactor stops, this radioactive decay heat continues, and reactor core cooling must be maintained. A detailed knowledge of these decays is required for the purposes of reactor design, fuel handling and shielding. Engineers rely on international databases that incorporate information about many hundreds of decays. A long-standing anomaly is present when attempting to use these databases to calculate the decay heat at short times (1000–3000 s). This is due to an inadequate knowledge of the characteristics of abundant short-lived fission products, largely because of the poor detection efficiency of the ubiquitous germanium detectors used in such studies. A Spanish–UK collaboration production of radioisotopes required for nuclear medicine and will provide beams for testing the latest designs of sensors for use in medical imaging. 2.6. The scientific challenges To give a flavour of the challenges and the open questions facing nuclear physicists in the next years and decades, listed here are 10 of the most exciting, outstanding questions in the field.

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has studied some of the key decays with a novel technique called total absorption spectroscopy, based on what is effectively a large gamma-ray calorimeter. The measurements of the decays of a series of technetium, niobium and molybdenum isotopes were carried out at Finland’s University of Jyvaskyla cyclotron laboratory using the very clean radioactive sources produced by the Ion Guide Isotope Separator On-Line and Penningtrap system. The new results clearly resolve the anomaly in the decay heat calculations, although studies are also needed of other species to provide the complete picture. This is an excellent example of how measurements and techniques developed for basic research can provide the data needed for application to fission reactors.

•Phys. Rev. Lett. 2010 105 202501 ●● What

are the phases of strongly interacting matter and what roles do they play in astrophysics? ●● What is the internal landscape of the nucleons? ●● What does QCD predict for the properties of strongly interacting matter? ●● What governs the transition of quarks and gluons into pions and nucleons? ●● What is the nature of the strong nuclear force 15

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that binds protons and neutrons into stable nuclei and rare isotopes? ●● What is the origin of simple patterns in complex nuclei? ●● What are the limits of nuclear stability? ●● Can all nuclei be described with one unified model? ●● What is the nature of neutron stars and dense nuclear matter? ●● What are the nuclear reactions that drive stars and stellar explosions? 2.7. Meeting the challenges: an overview Research in nuclear physics stands on the threshold of an exciting new era. Worldwide the subject is advancing rapidly. Major new facilities are being constructed or upgraded to address the challenges outlined in section 2, including FAIR (GSI, Germany), ISOLDE (CERN), SPIRAL II (GANIL, France), RIKEN (Japan), FRIB (USA), JLab (USA) and a number of underground facilities for studies in nuclear astrophysics. Further ahead, even more powerful isotope separation on-line (ISOL) facilities to produce beams of radioactive ions, such as EURISOL, are under consideration. ALICE at the Large Hadron Collider (LHC) is now operating, and RHIC is being upgraded. Together with the Compressed Baryonic Matter experiment at FAIR they will allow the exploration of the phase diagram of nuclear matter and shed light on what happened in the early universe in the transition from the QGP to the hadron-dominated world of today. As this next generation of major facilities is completed and becomes operational over the next decade, they will supply the beams of high-energy electrons, relativistic heavy ions and radioactive ions that are needed to address the scientific challenges. These three types of beam will allow the exploration and testing of whether QCD can adequately explain hadronic structure and whether the change from QGP to hadronic matter can be understood. Ultimately, the completely new intense beams of radioactive ions will transform knowledge of both nuclear structure and the astrophysical processes that depend on nuclear reactions and radioactive decays. Europe has a leading position in all of these endeavours. Why is access to this wide and diverse range of facilities needed? The answer is simple. To develop a comprehensive understanding of nuclei, their constituents and their interactions, there is a need

16

to probe and study manifestations of nuclear phenomena, from the short-lived fireball in ultrarelativistic collisions of heavy ions, through parton distributions in nucleons examined with high-energy electrons and photons, to reactions and decays of nuclei created with beams of stable and radioactive nuclei. To achieve this goal requires beams of the projectiles that match the appropriate energy and length scales associated with these processes. These facilities are important to UK nuclear physicists because it is here that future advances in the field are most likely to be made. Since 1993 the UK nuclear physics programme has had no national facility. It exists by securing time on other nations’ facilities on the basis of scientific excellence in the form of new ideas, new techniques and new forms of analysis and interpretation, and via the installation at those facilities of innovative and leading experimental devices. As one example of UK leadership and investment at an overseas facility, UK physicists have contributed heavily to state-of-the-art instrumentation and detectors installed at the cyclotron laboratory of the University of Jyvaskyla, Finland. This has greatly enhanced the experimental programme there and is an excellent example of this modus operandi. Unless the UK plays a significant part in the development and operation of these new facilities, UK nuclear physicists will be marginalised and will rapidly lose the leadership roles that they currently possess. They will have no real say in the future direction of the subject. This will also impact on its applications, most of which tend to spring from a close association with basic science. If fundamental research in nuclear physics continues to wither, the UK will need to rely on others to take both the basic science and its applications forward. Is it too late for the UK to play a part in these exciting developments? All of the above facilities still require capital funding to complete their equipment and, in some cases, the buildings housing them. The UK’s standing and influence in nuclear physics would be transformed if the UK was able to contribute capital funding to aid this completion. Strategic investment at this time can pay high dividends and influence the science that the UK can extract from the newest generation of nuclear physics facilities, including the two European Strategy Forum on Research Infrastructures (ESFRI) nuclear facilities – FAIR and SPIRAL II.

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The health of UK nuclear physics 3.1. Size of the UK nuclear physics community relative to other areas Information on the sizes of the different fields of physics in the UK can be obtained from a series of IOP surveys of academic appointments in physics covering the periods 2004–2008 [6], 1999–2004 [7] and 1995–1999 [8]. Table 1 shows the numbers extracted for nuclear physics compared with the other STFC science programme areas. The scope and methodologies of the surveys were slightly different; this introduces some error when comparing the two earliest years to later numbers. The size of the UK nuclear physics community has changed little over the period of the IOP surveys. Indeed, it appears that there has been no significant change in the size of the community over the past 25–30 years; anecdotal reports from the period of operation of the Nuclear Structure Facility at Daresbury Laboratory put the size of the community at around 60 scientists. A survey undertaken as part of the current review puts the community at 52 permanent academic staff in 2012. The period 2004–2008, for which directly comparable survey data were taken, indicates a moderate increase in the size of the community of 35%, largely in the number of research fellows. Academic staff numbers rose by 19%, which appears to be within the normal fluctuations given the historical record. This is in contrast to the large rises in academic numbers in particle physics and astronomy, 56% and 65%, respectively, with the total research communities increasing by 70% and 54%, respectively. These differences are likely to

be linked to funding levels and mechanisms (as discussed in section 3.4). The populations of these three fields of physics in the UK differ from those of comparable European countries. For example, the numbers of European astronomers can be estimated using the membership figures for the International Astronomical Union (IAU) [11] and compared to numbers of nuclear physicists [12, 13], on the assumption that the ratio of numbers of permanent academics to IAU membership is common across Europe. The nuclear physics and astronomy communities are roughly equal in France, Germany, Italy and Spain, but in the UK astronomers outnumber nuclear physicists by a factor of four to five. NuPECC surveyed the staff resources for nuclear physics across Europe in 1997 and 2006 [12], with the latter data subsequently revised in a Nuclear Physics Network (NuPNET) report [13]2. The data collected shed light on the position of nuclear physics in different countries, although care needs to be taken because the definition of nuclear physics is not universal across European funding agencies. The inclusion of some aspects of neutrino physics within the remit of nuclear physics or particle physics is probably the largest distortion. To make some comparison with the IOP reports discussed above, data are shown in figure 7 for the numbers of nuclear physicists with permanent contracts for selected European countries. The numbers for the UK (60 in 1997 and 63 in 2006) are not inconsistent with those from the IOP

2

The NuPECC 2006 data [12] were revised in the 2010 NuPNET report [13] but were not broken down into theorists and experimentalists. The revisions reveal some turnover in staff but also, given the changes in some figures, a difference in the interpretation of the original NuPECC data requests in some countries.

Table 1: Numbers of UK physicists in the STFC science programme areas. Data are shown for academics (professors, readers, senior lecturers and lecturers) and fellows (research fellows, experimental officers and senior experimental officers). Sources [6–8] Year

Nuclear physics

Particle physics

Astronomy

Total

Academics

Fellows

Total

Academics

Fellows

Total

Academics

Fellows

2008

65

50

15

278

221

57

407

307

100

2004

48

42

6

164

142

23

264

186

78

1999

42

153

241

1996

46

142

215

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surveys of academic appointments in physics [6–8]. The data appear to show that compared with countries similar in other ways (such as gross domestic product per capita and population) – France, Germany and Italy – the UK effort is limited and in fact smaller than the communities in Poland and Romania. The number in the UK is somewhat similar to the numbers in Spain and Hungary, although in both cases the balance of the programme is very different. Variations in the definition of “nuclear physics” between countries cannot account for the difference (see section 3.2). The size of the nuclear physics community in the UK appears to have remained static for many years and is small compared with other STFC science areas and compared with nuclear physics in other European countries. This unique feature has persisted for several decades and has no straightforward explanation. 3.2. The scope of the community Nuclear physics can be divided into a number of subfields, and figure 8 shows the distribution of staff resources (academics, fellows, postgraduate students and support staff) from the NuPECC

survey [12] for the UK compared with the rest of Europe. Some stark differences persist today. First, there are environmental differences: the UK has no home facilities, and neutrino physics in the UK is classified as particle physics. The UK science effort is clearly concentrated on nuclear structure, with less representation in the area of phases of nuclear matter connected with relativistic heavyion collisions. The proportions involved in hadron physics (QCD), nuclear astrophysics, accelerator and detector development, and applications of nuclear science are broadly similar to the European picture. The striking concentration of staff resources in the UK on nuclear structure is connected with the size of the community: focusing on a small range of research is the best way to provide global impact with limited resources and to avoid being spread too thinly. There is evidence in terms of research quality (see section 3.3) that this strategy has been very successful. Indeed, the new international nuclear facilities such as FAIR, RIKEN, FRIB and EURISOL opening in the next 15 years are directed largely to nuclear structure and astrophysics, and the UK community is well placed to realise the scientific potential that they will provide.

Figure 7: Numbers of nuclear physicists on permanent contracts in 2006 in European countries most active in the subject. Sources [12, 13] Belgium

NuPECC 2006 NuPNET 2010

Finland France Germany Italy Hungary Poland Romania Spain UK 0

18

50

100

150

200

250

300

350

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450

500


3 Figure 8: The percentages of staff resources working in the subfields of nuclear physics in the UK and across Europe in 2006. Source [12] QCD

Europe UK

phase of nuclear matter nuclear structure nuclei in the universe fundamental interactions applications of nuclear science user facilities accelerator and detector R&D 0

20

40

60

Figure 9: Staff with permanent contracts working in experimental and theoretical nuclear physics across Europe in 2006. Source [12] Belgium

theory experiment

Finland France Germany Italy Hungary Poland Romania Spain UK 0

100

200

As in most areas of physics, the researchers can often be classified into two distinct groups: those involved largely in experimental work and those chiefly concerned with theoretical developments. Both groups should exist in healthy symbiosis. Experimental physics is important in testing theoretical ideas, but it often produces unforeseen outcomes that drive the development of theory. Theoretical development can drive experimental

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efforts by making predictions of new phenomena, and input from theorists is important in enabling the interpretation of experimental data. The balance between theory and experiment in the UK is the most extreme in Europe, as indicated in figure 9, with only 9% of permanent staff theorists in 2006 compared with 27% in the rest of Europe [12]. This situation remains largely unaltered; a survey undertaken as part of the current review 19

3 Case study 1 Adam Garnsworthy: PhD in Experimental Nuclear Physics, University of Surrey, 2004–2007 Now: Research scientist, TRIUMF, Vancouver, Canada My PhD was a really great experience and launched me on a career in basic research. My PhD research project was centred on one experiment from the large RISING (Rare Isotope Investigations at GSI) campaign of experiments in Germany. The collaboration involved around 100 scientists from all over the world, which meant that I got to know many researchers in the field. I also spent one year working at the Wright Nuclear Structure Laboratory at Yale University in the USA. This gave me invaluable hands-on experience. Following my PhD I took up a twoyear postdoctoral position at TRIUMF, Canada’s national laboratory for nuclear and particle physics. When a tenuretrack research scientist position became

3

For example, the highest-impact results from nuclear physics are often published in Nature, Physical Review Letters or Physics Letters B, all of which are classified as “Physics, Multidisciplinary” within the Web of Knowledge database and do not appear in this analysis for “Physics, Nuclear”. Confusingly, IOP Publishing’s Journal of Physics G: Nuclear and Particle Physics is classified as a nuclear physics journal, and the publication of the biennial Review of Particle Physics in that journal has distorted the normalised citation data significantly for 2006 (see figure 11) [14].

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available at TRIUMF I was lucky enough to get the job and have now held the position for two and a half years. I am now joint principal investigator of a project called GRIFFIN to build a new state-of-the-art gamma-ray spectrometer for radioactive decay studies, costing C$8.7 m. My PhD was partially sponsored by Nexia Solutions Ltd (now the National Nuclear Laboratory). And each year I spent a week at the Sellafield site

working with the nuclear data group there. This showed me how the nuclear data generated in basic research is used and applied in real situations, such as the management of spent fuel rods from nuclear reactors. I also completed a training course in nuclear data evaluation, which has had a very positive impact on the way in which I present and report the research I do. The data-analysis skills I developed during my PhD are vital for the job I now have in experimental physics. The importance of competence in computer programming should not be underestimated. However, I think that the most valuable experiences during my PhD were the hands-on practical skills that I learned working in laboratories around the world. I consider this an essential aspect of any graduate student education and I would have been at a major disadvantage if I had not had the opportunity to work at major facilities during my PhD.

found eight theoreticians in 2012, compared with five in the NuPECC data from 2006 [12]. The IOP surveys [6, 7] indicate that the percentage of theorists in academic UK nuclear physics has fluctuated from 16% in 2004 to 24% in 2008. The 2012 figure stands at 15%, which is roughly the historical average over the past few years, indicating that there has been no recent action on the lack of UK theoretical support for the subject.

in the UK compared with elsewhere, outlined in section 3.2, necessitate caution when drawing detailed conclusions. However, some general lessons can be learned from bibliometric studies. IOP commissioned a recent report from Evidence, a business of Thomson Reuters, to analyse the bibliometric performance of physics and its sub-disciplines [14]. These data can be used to benchmark the performance of UK nuclear physics against international performance. It 3.3. The research output of the community should be noted that the analysis was performed The problem of assessing the research quality of only for the subset of a field’s output that appears a cohort is well known, but standard, if imperfect, in subject-specific journals through the use of bibliometric indicators are often employed. Cultural “journal categories” and misses publications in differences in publication and citation behaviour journals with wider readership3. With these caveats, UK performance can be often complicate comparisons. Nuclear physics, in common with many academic areas, displays a compared to other leading countries. Figure 10 shows the percentage share of world nuclear range of cultures, from papers with low numbers physics output in the period 2001–2010 for of authors from theory groups or bench-top selected countries. Despite the disparity in size of experiments, through to the collaborations of the order of 1000+ authors found in relativistic heavy- the UK community with European comparators, the UK contributes a significant proportion of world ion science. This results in a range of publication output. In 2006, where staff numbers are also and citation behaviours across nuclear physics. available [13], each tenured academic in the UK Hence, the differences in the scope of the subject

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contributed 0.1% of world nuclear physics output, compared with 0.03%, 0.05% and 0.02% for France, Germany and Italy, respectively. The normalised citation impact (nci) makes an attempt to remove the effect of both the variation of citation rate between fields and the accumulation of citations over time from bibliometric data. This is done by normalising raw citation rates to the world average citation rate per paper for the year and

journal category in which the paper was published. The latter effectively classifies the research field. The nci data, shown in figure 11, indicate that UK nuclear physics performance has increased over the past decade in common with other G7 countries. The blip in 2006 mentioned in footnote 3 is also apparent in this figure. Current UK nuclear physics performance is roughly similar to that of the USA, Germany and France, despite the disparity in

3

Figure 10: Percentage share of world output of papers in nuclear physics journals. Source [14] 30 25 20

UK USA Canada France Germany Italy China

15 10 5 0

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 11: Average normalised citation impact for papers in nuclear physics journals. Source [14] 2.5

2 UK USA Canada France Germany Italy China

1.5

1

A noticeable peak in normalised citation impact (nci) was observed for some countries in 2006. This was due to a single, highly cited, multiauthor article published that year, which received an exceptionally large number of citations. The nci for Canada in 2006 was 4.68.

0.5

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3 Case study 2 Alison Fletcher: PhD in Nuclear Physics, University of Manchester, 1999–2003 Now: Medical physicist, Clinical Research Imaging Centre, Edinburgh My PhD research was in high-spin gamma-ray spectroscopy. After my PhD I went into the NHS as a trainee medical physicist. I trained in the field of nuclear medicine and became a registered clinical scientist in 2008. Most of my work has been in PET (positron-emission tomography) where positron-emitting radiopharmaceuticals (e.g. 18F-FDG or 15 O-H2O) are used to image physiological processes such as tumour metabolism in cancer patients or blood flow to the heart in cardiology patients. This is a complex imaging modality that requires an indepth knowledge of radiation physics.

I am currently the lead physicist for PET at the Clinical Research Imaging Centre in Edinburgh. The centre is a joint collaboration between the NHS and the University of Edinburgh. We provide both a clinical service and perform R&D. My current job is to manage the scientific and technical aspects of the

numbers of scientists and other resources. The average nci hides the variation in impact of individual papers, which can be seen in the distribution of research outputs across nci performance. This is shown in figure 12, for two five-year periods, 2001–2005 and 2006–2010, compared with similar profiles for the other STFC science programme areas. In all areas, the nci profiles have improved over the decade, shifting to higher citation rates and lowering the numbers of uncited papers. From these data, it would appear that there are no significant differences in research quality between the STFC science programme areas of astronomy, nuclear and particle physics. There are differences in the volume of publication: using the staff numbers for 2008 [6], it can be estimated that each academic published 7.1, 8.6 and 4.6 papers per year in nuclear physics, astronomy and particle physics, respectively, for the period 2006–2010. Given the caveats associated with bibliometric analyses, caution must be taken against drawing too-detailed conclusions. However, these data reveal that UK nuclear physics output performance is at least as good as that of European competitors, despite the lower level of available resources. The publication rates per individual in the UK appear to be significantly higher than those 22

service as part of a multidisciplinary team. We undertake a large number of clinical research projects. I provide the scientific input to the development of these new procedures and ongoing support to the clinical research teams. I am also responsible for the teaching and training of various professional groups, managing staff and providing guidance on radiation safety and regulatory standards. My PhD has proven invaluable in equipping me with the skills to perform my job. Overall, my post requires a thorough knowledge of radiation physics, which I acquired during my research. However, I have found that other skills that I acquired during my PhD, such as project management, data analysis, communication and presentation skills, are also invaluable.

in other countries. The bibliometric quality of nuclear physics is similar to that in other fields of physics within the UK. This performance has been sustained over the last decade. It should be noted that nuclear physics (in common with other STFC science areas) has a long lead time, often five-plus years from the investment in equipment, through the execution, analysis and interpretation of experiments, to the publication of papers. Indeed, this feature was one of the reasons for moving nuclear physics into the STFC funding remit upon the research council’s creation in 2007. The outputs considered in the IOP/Evidence report [14] were therefore generated before the effect of reductions in STFC support in the 2007 and 2010 CSRs on research outputs become fully apparent, and thus should be monitored. 3.4. Funding The funding sources for nuclear physics are largely similar to those for the wider subject of physics in general, highlighted in a recent IOP report [15]. For physics, 79% of research funding is external, and 80% of that comes from the research councils. Physics and its fields have been identified for some time as underpinning more applied disciplines. The subjects of research are further from the market than other fields and consequently attract

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3 Figure 12: Normalised citation impact (nci) profiles for papers in journals related to the STFC science programme areas; the upper plot is for the period 2001–2005 and the lower plot for 2006–2010. Source [14]

uncited

nci ≥1 nuclear physics astronomy particle physics

nci ≥4 0

5

10

15

20

25

30

35

40

uncited

nci ≥1 nuclear physics astronomy particle physics

nci ≥4 0

5

10

15

less direct income from commerce and industry. It should be remembered that important direct connections do arise, particularly in the technology that was initially developed for curiosity-driven research. The serendipitous nature of such endeavours has long been recognised (for examples see [16, 17]). Research funding for nuclear physics is therefore largely from research council sources for the main thrust of the academic field; nuclear physicists attract some industrial funding, but it is focused in specific applied projects (see the examples in boxes in section 2). Given that most of the funding in nuclear physics originates from the research councils, some

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25

30

35

40

background is needed to understand the current position of the field in RCUK. From 1994 to 2007, the EPSRC held responsibility for nuclear physics funding, initially as a managed programme of rolling grants that was soon integrated into the Physics Responsive Mode Panel in a move towards projectorientated funding4. The long lead times associated with nuclear physics research and the potential risks that responsive mode presents for such a subject were recognised and resulted in a transfer of responsibility for nuclear physics to the newly created STFC in 2007. In the STFC it could be treated in the same way as the other science programme areas with similar characteristics, such as astronomy

4

Responsive mode involves grant proposals across the EPSRC physics remit being sent to peerreview panels that meet regularly during the year. The mechanism tensions different areas of physics at the individual project level. The result is a very rapid and responsive process, but it operates without the longer-term strategic view at the subdiscipline level that forms part of the funding planning processes at STFC and its predecessor the Particle Physics and Astronomy Research Council.

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3 Table 2: STFC resource budget for nuclear physics. Source [18] 2011/12 £m

2012/13 £m

2013/14 £m

2014/15 £m

Development

1.69

1.53

1.68

1.89

Exploitation

3.53

3.18

4.83

5.30

Total for nuclear physics research

5.22

4.71

6.51

7.19

Studentships and fellowships

1.09

1.08

1.07

1.09

Total of all nuclear physics activity

6.31

5.79

7.58

8.28

and particle physics. The subsequent financial difficulties within the STFC have resulted in a very difficult funding environment for nuclear physics, in common with the other STFC science programmes. An estimate of the current research council funding levels for nuclear physics can be obtained from the recent STFC Delivery Plan [18]; the planned resource budgets in 2011 for the remainder of the CSR period are shown in table 2. Over the period an average of £5.9 m is available for research, excluding education and training. It is more difficult to obtain accurate numbers for earlier levels of funding for nuclear physics. Research council figures are available for 2007, the year after transfer from the EPSRC, quoted in a NuPNET report [13] as €11.7 m, equivalent to around £8.4 m, for the national funding source in 2007. This corresponds fairly well to the £8.7 m quoted in the EPSRC/STFC Review of Nuclear Physics and Nuclear Engineering [3] for nuclear physics funding, which excluded research students and fellowships. A similar number was submitted to the Wakeham review of physics [19]. The research funding level for 2007 is therefore estimated to be of the order of £8.5 m. Uncertainties in estimating funding levels further back in time increase. From the Shotter review of nuclear physics [20], it can be seen that the baseline funding for 1996/1997 and 1997/1998 was £6.1 m per year including education and training, with the research element being £5.3 m, which, converted to 2007 prices, lies in the range of £6.5 m to £9.0 m [21], indicating little change in the value of the funding over that decade. To within the uncertainties expressed above, the value of nuclear physics funding (excluding education and training) appears to have remained 24

fairly constant from the Nuclear Structure Facility closure to 2007; this corresponds to a facevalue increase of 58% between 1996/1997 and 2006/2007 to around £8.5 m. It should be noted that for most of this period there was no strategic view of the funding levels for nuclear physics; the levels were reached during the period after 1997/1998 via piecemeal competition of responsive-mode grants at individual EPSRC physics panels, and funding levels were not reached by a considered strategic analysis. The financial issues within the STFC resulting from the CSR in 2007 have led to a reduction to an average of £5.9 m per year in 2011–2015. The evolution of nuclear physics funding in the past decade is in sharp contrast to that experienced across the rest of the physical sciences. An IOP report on research income indicates that, across the whole of physics, research council funding rose by 74% from 2004/2005 to 2009/2010 [15]. The dramatic rise in the size of some physics communities noted above, particularly the ex-Particle Physics and Astronomy Research Council-funded areas where strategic funding decisions were made and long-term stability thus generated, appears to coincide with this period. While all STFC science areas have suffered badly since 2007 as a result of the STFC’s financial predicament, there is no evidence that nuclear physics enjoyed a similar uplift in funds beforehand. It is also noted that the historical figures available suggest that the nuclear physics research and education, and training activities have been funded at the same ratio of around 85:15 for at least the past 15 years. Some information is available on the bottomline figures for nuclear physics research funding

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3 Case study 3 Andrew Petts: PhD in Nuclear Physics, University of Liverpool, 2006–2010 Now: Reactor physicist/nuclear safety engineer, EDF Energy My PhD research centred on measuring transition matrix elements of neutrondeficient mercury isotopes and investigating shape co-existence in that region of the nuclear landscape. After completing my PhD I had hoped to stay in academia, but with the severe cuts to fundamental nuclear research, I decided to take a job in industry. My current role as a reactor physicist for EDF Energy utilises many of the skills that I developed during my academic research. The fundamental knowledge of nuclear physics and gamma-ray spectroscopy acquired during my PhD has been invaluable. I regularly analyse reactor data, including isotope spectroscopy, and report on the results.

I have to report to my peers and with non-subject-expert managers. I believe that the practice of writing journal articles, and particularly presenting at conferences to mixed audiences, gave me a head start in this area. The practical techniques and fundamental knowledge of gamma-ray spectroscopy are the areas of my PhD

in various European countries [13]. However, it is difficult to reach any firm conclusions given the variation in financial practices and financial definitions across European nations. 3.5. Education, training and inspiration The nuclear physics community provides graduate training via two routes. One is in doctoral research degrees based largely on the core academic nuclear physics research. The other route is via the provision of a variety of master’s degree programmes, the most popular of which are associated with applications of nuclear physics, in particular nuclear science and technology, nuclear power and reactors, radiometrics (radiation detection and measurement), and radiation protection. Although the main thrust of UK academic nuclear physics research is in areas of curiosity-driven science, the field underpins all of nuclear science from power to medical applications. As a result the subject plays a vital role in the provision of trained people for industries working with applications in nuclear science, as well as a number of related areas. Since 2003, approximately 24 PhD students per year have graduated with theses based on nuclear

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that I utilise most in my current role. In my capacity as a reactor physicist I am in charge of the system used to monitor the coolant activity of the reactors on-site. This involves maintenance and set-up of HPGe (high-purity germanium) detectors and isotope analysis via gamma-ray spectroscopy. The analysis of fission products is of great importance because it informs us about the state of the fuel inside the reactor. My knowledge of gammaray spectroscopy and fundamental nuclear properties helps greatly with the evaluation of data. A project that really utilised my PhD experiences and experimental skills involved me in the designing of a bespoke piece of monitoring equipment for fuel integrity measurements. My academic training was integral to the success of this particular project and has been to the advancement of my career to date.

physics. In common with many postgraduate research degrees across the physical sciences, such graduates have a number of transferable research skills at the highest levels. Training in nuclear physics research generates a number of unique skills, associated with both the specifics of the subject and the research culture, that are of particular benefit to sectors of the UK economy. More details can be found in Appendix 3, but in summary, graduating PhD students in nuclear physics are particularly skilled in: ●● Detailed and high-level knowledge of radiation detection and instrumentation, and of nuclear decay and reactions. ●● Numerical analysis, modelling and simulation, especially radiation transport through matter. ●● Working in large internationally distributed collaborations. Case studies of nuclear physics PhD graduates can be seen throughout section 3. Academic nuclear physics research therefore provides an important flow of independently trained, highly skilled people into the energy sector (particularly the nuclear industry), medical-related areas, and other industries and businesses that 25

3

require high levels of numerical analysis, modelling and simulation. This is reflected in the first employment destinations for graduating nuclear physics PhD students for the period since 2003, which have been compiled as part of this review and are shown in figure 13. The destination data clearly show the effect of the recent financial crisis and the resulting economic problems: the numbers entering financial jobs have decreased and the proportion choosing postdoctoral research has increased since 2008. The vast majority of non-academic jobs are within UK industry, with very few relocating abroad. A significant number of graduates undertake postdoctoral research, mainly within nuclear physics, but often outside the UK. However, the number finally obtaining permanent academic positions is limited, so that the majority of this cohort ultimately end up in non-academic careers at a variety of points. This report did survey postdoctoral research associate destinations, but the data are less comprehensive than for the PhD destinations. It appears that the main destinations for postdoctoral researchers are largely similar to the PhD graduates leaving academia, commonly to the nuclear industry, finance, medical areas or other industry, and mainly to positions within the UK. It should be noted that the application of the STFC algorithm for determining the numbers of PhD studentships to nuclear physics, introduced in 2012, has resulted in a sharp fall in the number of students supported by a research council. This reduction has not yet filtered through to graduation and is likely to temper the numbers by up to 50%. As noted by the recent EPSRC/STFC Review [3],

masters-level programmes provided by the nuclear physics community also supply an important flow of trained personnel into industries related to nuclear science and radiation detection and measurement. The four largest programmes according to data [3] are: ●● Nuclear Science and Technology (Nuclear Technology Education Consortium) 15–20 full-time students per year alongside a similar number of part-time students from industry. ●● Physics and Technology of Nuclear Reactors (Birmingham) 30–40 students per year. ●● Radiometrics: Instrumentation and Modelling (Liverpool) 5–10 students per year. ●● Radiation and Environmental Protection (Surrey) 20–25 students per year. There are other MSc courses, such as the MSc in Medical Physics at Surrey, where nuclear physics academics teach significant parts of the curriculum. Such MSc courses exist because of the availability of nuclear physics academics to teach them, so that there is an indirect benefit from nuclear physics research. On a more general level, the wonder stimulated in young people by basic research in fundamental science inspires them to enter and progress in scientific education. Interest in nuclear physics, in common with the other STFC science programmes, is often quoted by young people as one of the key motivators to study science, even if they ultimately study another area such as life sciences, engineering or work in industry. For example, a 2007 survey of more than 800 physics undergraduates’ interests [22] and

Figure 13: Destinations of PhD graduates in nuclear physics since 2003

academic

unknown other employment

civil service

charities

computing

nuclear

education

medical

finance other industry

other business and consultancy

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3 Case study 4 Philippa Marley: PhD in Nuclear Physics, University of York, 2006–2011 Now: Staff scientist, Kromek My PhD was in the field of high-resolution gamma-ray spectroscopy. My particular research focused on the decay pathways of radiative capture reactions of importance in astrophysics. During my studies I was fortunate enough to participate in experiments at world-class facilities such as CERN-ISOLDE and national laboratories in the USA. This not only allowed me to gather experience working with the best radiation detector arrays in the world, but also the personal skills related to working in large, culturally diverse collaborations. I had hoped to continue in academia but with my partner having a PhD in the same field and the lack of positions due to the funding crisis, it proved incompatible with family life. Initially I was concerned that my research was too esoteric to transfer to the world of industry. However, this proved to be unfounded because I was fortunate enough to find a great role

that combines the freedom to pursue fulfilling research with the benefits of bringing innovative products to market. My current position is as a research scientist at Kromek, a spin-off company from Durham University that develops CdZnTe radiation detectors. During the 18 months that I have worked there, the focus has switched from existing products in the security field to the development of new radiation detectors for emerging markets. My job makes good use of my background in gamma-ray spectroscopy and

involves the development of innovative radiation-detection products, including analysis algorithms. The recent events in Fukushima have changed the way that many people think about radiation on a day-to-day basis, both on a large industrial scale and a more personal level. This has led to interesting challenges to develop products to meet these needs as they evolve both now and in the future. This kind of work requires me to utilise many skills, both subject-specific and more general. My background in gamma-ray spectroscopy plays a large role along with data-analysis skills. Computer programming has proved to be very useful as has my experience of communicating to non-expert audiences. A large part of my current role involves assessing the physics constraints of a particular situation and conveying these concepts clearly and concisely to non-scientists. Overall, despite my initial worries that a PhD had made my skill set too narrow for a role outside academia, I have found a job that I am well suited to and really enjoy.

motivations found that for first-year students particles and quantum phenomena (72%), nuclear physics (61%) and astrophysics (53%) had provided inspiration for them to join the course, and 90% of students expressed a significant interest in at least one of these areas. The same survey revealed a continuing interest in the areas, with 82% having a specific interest in nuclear physics and high percentages also in particle physics (89%) and astrophysics/cosmology (73%).

Overall, it is clear that UK nuclear physics did not enjoy the general boost in science funding in the period up to 2008 but still took a full share of the cuts applied to all STFC science programmes following the 2007 and 2010 CSRs. It is too early for the effects of these cuts to be seen in the available evidence on research outputs. Nuclear physics has a particular economic importance for nuclear, medical, finance and other areas of industry by supplying a steady stream of postgraduate students trained with a unique skill 3.6. Summary set. There is evidence that nuclear physics is an The evidence suggests that UK nuclear physics is attractive hook enticing young people into science a small but vibrant community, focusing efforts in in general, as well as into nuclear science and the important topical areas within the field. It punches physics and engineering associated with nuclear above its weight in volume and quality of scientific power. The reduction in the number of PhD students research outputs, competing well with other supported by a research council is too recent countries in nuclear physics and with similar fields of to assess its effects, but it should be carefully physics within the UK. Nuclear physics in the UK has monitored. Given the dearth of skilled people in the consistently operated at the highest international nuclear area, the effects are only likely to add to the levels despite comparatively limited resources. skills shortage.

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Conclusions and recommendations This section summarises the panel’s conclusions based on sections 2 and 3. The first and most important conclusion derives from the brief description of contemporary nuclear physics given in section 2 and the many recent reports, including those published by a number of international bodies [1, 4], IOP [16] and the NPAP set up by the STFC [2]. Together they provide a picture of a vibrant and rapidly moving research scene in nuclear physics worldwide. The subject exists because human beings are curious and eager to discover the answers to a whole series of fundamental questions. Efforts to answer them have led to many applications that have transformed our lives and improved the quality of life of our citizens and will continue to do so as curiosity-driven science is pursued. Tools for medical diagnosis and therapy have been and are being developed. In the UK roughly one-sixth of the population will receive radiation therapy at some point in their lives. Fission-based reactors currently provide 16% of the electricity consumed in the UK, and the government has given the private sector the green light to build a new fleet of reactors in England and Wales. Nuclear physics applications also play a significant role in defence and national security. The panel concludes that nuclear physics is a vital component of the UK’s research activity. It is important in its own right because of the fundamental questions that it aims to answer. It is also important because new technologies, products and services flow from the knowledge acquired in that quest. The UK cannot lead the world in every aspect of nuclear physics. However, the UK has to be competitive globally, and needs a community of sufficient size and strength to exploit the basic science to its advantage in developing new technologies and to train the cadre of scientists needed by the UK in areas such as healthcare, the nuclear industry, defence and national security. In terms of the health of nuclear physics research in the UK, the panel has reviewed the evidence available and concludes that: ●● If the field is to develop and diversify, improve the capability in terms of theory and train the people the UK needs, then future funding should be increased. This is important in terms

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of maintaining the quality of UK nuclear physics research, creating the skills and expertise that allow applications to flourish and producing trained people vital to UK plc. In doing this it will be important to maintain the strength of effort in nuclear structure as well as ensure that the UK’s role in hadron physics, nuclear astrophysics and studies of unconfined nuclear matter is strengthened and expanded. ●● The research output of the UK nuclear physics community is healthy both in terms of the volume of papers published per academic and in the quality of its publications in comparison with major competitors on the world stage and with other areas of physics in the UK. Both the volume and the quality of papers have been maintained in the period since 2005 when the last international review of UK physics and astronomy was undertaken. This conclusion is tempered by the fact that the long timescale from laboratory to publication in the subject means that it is based on the more generous funding regime of a few years ago and that it will be difficult to maintain this level of international excellence with the much-reduced funding now available. In terms of the programme of research to be pursued, the panel agrees that it: ●● Should be broadly along the lines proposed in the report by NPAP [2]. ●● Would benefit from greater breadth. This cannot be attained by cutting back on the dominant area of nuclear structure research, which is already at a funding cusp and cannot sustain further funding erosion, but by ensuring that growth in future should enhance other areas. ●● Needs increased numbers of people and funding to strengthen the basic science and allow more effort to be devoted to the application of the expertise, knowledge and skills of the nuclear physics community to the undoubted benefit of the UK. Thus, the panel concludes that the UK needs a first-class research programme in nuclear physics to maintain its scientific standing, exploit and develop new technologies, and provide the trained personnel needed in the areas of nuclear energy,

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reactor decommissioning, medicine, national security, wider industry and maintenance of the nuclear deterrent. As seen clearly in section 3 the amount currently invested in the subject in the UK is out of line with competitors, and given the quality of the UK community’s work, it should be much higher. It would be simple but naive to recommend that the UK immediately invests more in nuclear physics. Although this would be sensible and provide a good return on the investment, the STFC should look to change this situation over a period to the benefit of the UK in terms of the return in basic research, applications and the trained people it produces. Given the current economic situation the panel’s approach was to look first at what the academic community can do to improve matters without extra funding, and if the measures suggested below are successful the panel believes that increased funding would follow over a longer period. It is essential for the UK that the STFC addresses the underfunding of nuclear physics at the earliest opportunity. On the basis of the panel’s visits to all of the UK academic nuclear physics groups, the answers received to the questionnaires and the information available in the literature made it possible to readily discern a series of issues that will threaten, along with the lack of investment and the recent “emergency” reductions in funding, the volume and quality of future UK nuclear physics output, unless steps are taken now to address them.

Astrophysics and Reactions (NuSTAR). The community needs to make a concerted effort to obtain funding for other projects. These projects will not only pave the way for future experimental activity but also preserve the expertise built up in various areas over many years. It is this expertise and associated skills that have allowed the community to partially “pay its way” at the overseas facilities where its research is carried out. This would address some of the issues highlighted in the panel’s group visits, such as the decay of the community infrastructure set up after the closure of the Nuclear Structure Facility at Daresbury Laboratory and the perceived lack of leadership in the community. The proposed COE should also take responsibility for ensuring first-class training for all nuclear physics PhD students. Following a change in the algorithm determining how research studentships are allocated by the STFC, there has been a sharp reduction in the numbers of STFC-funded students in nuclear physics. Typically there will now be about a dozen new STFC-funded students per annum for all of the groups. This is, of course, supplemented by students funded from other sources. Although good training is not impossible under these circumstances, where each group has only a handful of students, it is not ideal. In addition, the answers to the questionnaires suggested that UK PhD students engaged in experimental work no longer receive the “hands on” training they require to make them fully rounded experimenters. 4.1. Forming a Centre of Excellence Increasingly, theory students do not obtain the full The panel concludes that UK nuclear physics would and proper formal training they need, and this will be greatly strengthened by much closer linkage apply to the theoretical background that students of all of the UK nuclear physics groups. Thus, the in experiment also need. It should be noted that panel’s first recommendation is that they join to these comments no doubt apply to some students form a UK Centre of Excellence (COE) in nuclear but not all: currently it will vary from place to place physics. The community should implement this and group to group. To deal with this problem the recommendation at the earliest opportunity with panel recommends that the initial and formal the support of the IOP Nuclear Physics group. aspects of PhD education and training are carried The COE would be a collective grouping of all out on a UK-wide basis under the auspices of the nuclear physicists across the UK with the aim of COE. The details of the organisation and delivery of providing internal support to the whole community such training, whether it is web-based or uses live in a number of areas, acting as a virtual focus for video sessions or some combination of the two, is the community’s activities and as a voice for the a matter for future discussion or consideration. Any community in dealing with external agencies. The electronically delivered training should be backed COE would allow a coherent, collegiate approach up by some face-to-face contact, and the overall to tackling the lack of breadth in the experimental scheme should integrate the long-running biennial programme and allow a communal approach to Nuclear Physics School. Initial hands-on training for bids for projects to the STFC and other funding experimenters should also be part of the scheme, agencies. At the time of writing, only one STFC and the COE should attempt to maximise the use project is funded, namely Nuclear Structure of any national resources for this purpose and any

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resources for training available at the international facilities where there is a strong UK presence. A good example here is the cyclotron laboratory at the University of Jyvaskyla, Finland, where there has been a strong UK programme in laser and gamma spectroscopy, and students receive sound training in experimental techniques. The formation of a strategic alliance with a group of European laboratories for this purpose has the potential to help with this aspect of training and might lead to a bid for a Marie Curie Research Training Network. It should be noted that none of this would obviate the need for high-quality supervision of the individual student’s research. 4.2. Raising the profile of nuclear physics research and applications One point highlighted in all of the panel’s meetings with the nuclear physics community is that the community as a whole has failed to capitalise on the undoubted excitement in its science by communicating it to others. This has a profound effect on how the subject is viewed outside the community, with associated consequences for the funding it receives. A number of individuals in the community have devoted time to promoting nuclear physics and science more generally, but the community overall has no ethos of proactive reporting of highlights of its research beyond the international academic circuit. If the subject is to receive the funding it needs to work at the forefront of research worldwide and to contribute its skills properly to the applications of nuclear physics, then this must change. Doing excellent work is not enough: the wider world needs to know about it if there is to be enthusiasm about funding it. There are a variety of ways in which this may be improved. The essential step is that the community must focus on the challenge of promoting its science. The panel recommends that the proposed COE ensures that publicity/communications concerning UK nuclear physics are effective and that it should make good use of the STFC communications office/ group. It will be essential that the community uses all outlets, and the COE should make sure that the STFC communications group is familiar with the science and its applications so that it can readily assimilate and deal with new press stories. Nuclear physics has been a prolific source of applications, and there are now whole branches of science based on the phenomena discovered and the techniques developed to study them. In addition to their basic research, most of the

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UK groups are involved in applying their science to healthcare, security, and nuclear power and decommissioning. On the whole these collaborations have been developed on an ad-hoc basis with individual companies. This fails to maximise the potential for application of the skills possessed by the whole community. Accordingly, the panel recommends that as part of the COE the groups combine to form a “one-stop” shop as a focal point for interaction with potential users of their skills and to promote interactions with industry. This would provide a showcase for their skills and allow them to form consortia with partners to bid for funds from the EU or EPSRC, or other agencies. Such consortia are strongly favoured by the funding agencies. In this context, the division of responsibility between the STFC and EPSRC for basic and applied research on nuclear fission is an unfortunate one. It tends to result in the isolation of nuclear physics from nuclear science generally. If, for example, the STFC fails to fund nuclear physics at a level at which excellence can be maintained internationally in the basic science and fails to play a full role in applications linked to nuclear fission, then the UK will be illserved at a time when research related to nuclear fission is of growing importance. The COE can play a role in mitigating the negative aspects of the boundaries within RCUK. 4.3. Additional theory group All of the above recommendations can be implemented without extra external funding. However, the next recommendation from the panel does require additional funding from RCUK. It is evident that there are too few theorists in nuclear physics in the UK. Quite apart from the obvious comparisons with other European nations, it is clear that the absolute numbers are too small and are concentrated in two places: Surrey and Manchester. This means that most of the experimental community has no day-to-day contact with theoreticians. The theorists play three major roles: providing leadership in the subject, developing new mathematical models and helping to interpret experimental results. The small numbers of people involved in the UK mean that these roles are often not fulfilled. As a result, the panel recommends that the STFC and RCUK take the initiative to create a new theory group at an institution other than Surrey or Manchester. This can be done in a variety of ways. For example, a similar path may be followed to the Finnish one of

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establishing the Finland Distinguished Professor Programme (www.fidipro.fi/). However it is done, the panel is of the view that the new group should be established by competition, with the successful institution pledging half the funds to match those put forward by the STFC and RCUK for a period of, for example, five years. The new group would require at least three postdoctoral positions and a similar number of studentships over such a five-year period in addition to the necessary faculty positions. The new theory group would, together with the existing theory groups at Manchester and Surrey, constitute a vital part of the COE. In addition to helping to revitalise nuclear theory in the UK, they would play a key role in a) the training of all graduate students in nuclear physics, b) the organisation and co-ordination of visits by theorists to the purely experimental groups and c) the organisation of a strong visitor programme for the entire community.

to the UK of a strong and healthy nuclear physics community is the trained personnel that it produces. Many published reports identify that the UK has a significant “nuclear skills gap”. A recent report by the Birmingham Policy Commission [5] summarises the situation. The shortages are spread across all of nuclear science including nuclear physics. A particular need is for skilled people to help in building a new reactor fleet and in dealing with the legacies of the reactors and other nuclear facilities that have closed or will close in the next decade. The report leaves no doubt that there is a problem. The UK nuclear physics community provides trained personnel to help in filling this gap and, more generally, provides people with a background in nuclear physics. In the view of the panel it is essential that sufficient trained people at MSc and PhD levels are produced.

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4.5. Recommendations from the 2009 4.4. Facilities EPSRC/STFC review There are currently no domestic facilities for nuclear The 2009 EPSRC/STFC review [3], chaired by physics research in the UK. Neither does the UK Dame Sue Ion, was concerned with both nuclear have any formal arrangements for membership physics and nuclear engineering. The main of overseas facilities other than CERN, which is of questions addressed in the current IOP report, particular importance to those studying relativistic namely the health of UK nuclear physics and the heavy-ion collisions at the LHC. UK physicists are provisions needed to make it flourish, were outside also involved with ISOLDE and the neutron time-of- its remit. To the best of the knowledge of the panel, flight facility at CERN. In general, having no formal many of the recommendations of the EPSRC/ membership of any of the major facilities currently STFC review have been implemented. However, a under construction means that the UK community number of them have either not been implemented has little influence on the future direction of the or not been pursued actively enough. In particular, field. As indicated in section 2.2, the panel believes the panel notes the entirely unsatisfactory division that strategic capital investment at this time can of basic and applied nuclear physics between the restore the UK to a leading position and help to EPSRC and STFC. The panel considers that this is drive the field forwards. Although the community unlikely to lead to sensible decision making and has survived at the forefront of science output, to ensuring that the nuclear physics community since the closure of the last world-class facility plays a full part in meeting the UK’s needs in the on UK soil, Daresbury’s Nuclear Structure Facility, nuclear industry, healthcare, defence and national in 1993, the UK faces the real likelihood of being security. In this context the panel believes that the progressively marginalised in Europe as other following review recommendations have not been countries invest in new technology and facilities. followed up properly. These (numbered 6–10 in the The strategic answer is to inject capital investment EPSRC/STFC review [3]) should be pursued with into one or more of the key developments nearing some urgency. completion in a way that significantly enhances the capability of that facility. Again, the panel is of the Recommendation 6 view that investment in a number of facilities would The panel noted with some concern the issue of pay dividends. The panel recommends that as a funding for taught masters courses in nuclear minimum the STFC negotiates formal association science and technology. An appropriate funding with FAIR and ensures the UK is in a position to join stream should be established for these courses EURISOL if it becomes a funded project. by the spring of 2010. The panel recommends In the panel’s view, one of the major benefits that the research councils should work proactively

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Recommendation 9 The panel felt that there is greater scope for the nuclear physics community to capitalise on application areas generally. The panel therefore Recommendation 7 recommends that the nuclear physics and nuclear In addition to recommendation 6, the panel engineering communities seek better research recommends that the nuclear physics and nuclear links in areas with potential for future economic engineering communities, assisted by the research impact. councils, should proactively engage with industry to seek out opportunities for further funding for taught Recommendation 10 masters courses, particularly through provision of The panel commented on the need for a vibrant Continued Professional Development courses. research base and a pool of trained UK nationals when considering the UK’s future energy security. Recommendation 8 The panel recommends that the research councils The panel recommends that the research councils work in concert to optimise the links between jointly and proactively engage with the nuclear nuclear engineering, nuclear physics and industry. physics community and other funding agencies to identify the challenges and opportunities in The formation of the COE would make the the areas of nuclear data, healthcare, nuclear implementation of these and any similar forensics and homeland security where nuclear recommendations/initiatives in the future physics can play a key role, and capitalise on the much easier. The panel believes that all of these need for technology solutions in these areas. recommendations are important, and recommends It was recognised that blue-skies research and that the COE plays an active role, in partnership development spawns novel ideas and technologies, with the STFC and EPSRC, in ensuring that the and that challenge-led research and development recommendations of the EPSRC/STFC Review, can bring these technologies closer to the particularly recommendations 6–10 in its report, marketplace. are implemented. with the research community to highlight the issue to relevant government departments and work towards a resolution.

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Summary of recommendations

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The panel recommends that the STFC takes steps to ensure that UK nuclear physics is funded sufficiently well to maintain scientific excellence, to diversify, to improve capability in terms of theory, to play a full role in applications and to train the people that the UK needs.

The panel recommends that all of the UK academic nuclear physics groups join to form a UK COE in nuclear physics.

• T he panel recommends that the initial and formal aspects of PhD education and training are carried out on a UK-wide basis under the auspices of the COE.

• T he panel recommends that the COE ensures that publicity/communications about

nuclear physics are effective and that the COE and all of the component UK groups in nuclear physics are proactive in publicising nuclear physics in general.

• T he panel recommends that the COE acts as a “one-stop” shop to provide a focal point for interaction with potential users of the skills of the nuclear physics community.

• T he panel recommends that the COE plays an active role, in partnership with the

STFC and EPSRC, in ensuring that the recommendations of the EPSRC/STFC review, particularly recommendations 6–10 in its report, are implemented.

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The panel recommends that the STFC and RCUK take the initiative to create a new theory group at an institution other than Surrey or Manchester, with the location of the new group being determined by competition, and supported by STFC and by matching funds from the successful institution. The panel recommends that the STFC negotiates formal association with FAIR and ensures that the UK is in a position to join EURISOL if it becomes a funded project.


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References [1] www.nupecc.org/lrp2010/Documents/lrp2010_final_hires.pdf [2] www.dropbox.com/s/y0l2lcr7mmfngwm/Report_1.doc [3] EPSRC/STFC Review of Nuclear Physics and Nuclear Engineering 2009 chaired by Dame Sue Ion [4] http://sites.nationalacademies.org/BPA/BPA_069589 [5] w ww.birmingham.ac.uk/research/impact/policy-commissions/nuclear/reportlaunch.aspx [6] S urvey of Academic Appointments in Physics 2004–2008: An Institute of Physics Report, January 2010 [7] S urvey of Academic Appointments in Physics 1999–2004: An Institute of Physics Report, February 2005 [8] 15.2 Statistics Paper 3: New Academic Appointments: An Institute of Physics Briefing Note, November 1999 [9] A GATA S Akkoyun et al. 2012 Nuclear Instruments and Methods in Physics Research A 668 26–58 [10] www.scapa.ac.uk/?page_id=53 [11] www.iau.org/administration/membership/national/ [12] N uPECC Survey 2006 on Resources in Nuclear Physics Research in NuPECC Member Countries [13] NuPNET Report 2010 Overview of the Resources and International Collaborations in Nuclear Physics in Europe [14] B ibliometric Evaluation and International Benchmarking of the UK’s Physics Research, report prepared for the Institute of Physics by Evidence, Thomson Reuters, January 2012 [15] S tatistical Report: Research Income of Physics Cost Centres in UK Higher Education Institutions: An Institute of Physics Report, February 2012 [16] N uclear Physics and Technology – Inside the Atom: An Institute of Physics Report, 2010 [17] R ising Above the Gathering Storm: Energizing and Employing America for a Brighter Economic Future 2007 National Academies Press [18] S TFC Delivery Plan 2011/12–2014/15: Impact Through Inspiration and Innovation, 2011 [19] RCUK Review of UK Physics 2009 chaired by Prof. Bill Wakeham [20] Review of Nuclear Physics 1996 report of a review panel chaired by A N Shotter [21] www.measuringworth.com/ [22] Particle Physics – It Matters: An Institute of Physics Report, 2009

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Appendix 1: Membership of the panel

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Panel members William Gelletly Jim Al-Khalili Ani Aprahamian Rick Casten Philippe Chomaz Alan Copestake Sean Freeman Paul Howarth David Ireland David Jenkins John Priestland

University of Surrey, UK, and chair of the panel University of Surrey, UK University of Notre Dame, USA Yale University, USA CEA Saclay, France Rolls-Royce, UK University of Manchester, UK National Nuclear Laboratory, UK University of Glasgow, UK University of York, UK Hyder Consulting, UK

The Institute of Physics provided the secretariat for the panel: Philip Diamond, Tajinder Panesor and Sophie Robinson.

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Appendix 2: Glossary AGATA

Advanced Gamma Tracking Array An array of germanium gamma-ray detectors, each of which is sensitive to the position of photon interactions. It is designed specifically to allow the direction of incidence of the photons to be determined and used to correct for the Doppler shift when they are emitted from a moving nucleus.

ALICE

Large Ion Collider Experiment A Heavy-ion detector to study products of nucleus–nucleus collisions at Large Hadron Collider energies.

CBM

ompressed Baryonic Matter C Experiment at GSI’s FAIR to study highly compressed nuclear matter. Matter in this form exists in neutron stars and the cores of supernovae explosions.

CERN

The European Organization for Nuclear Research (Geneva, Switzerland) European laboratory, established by treaty. It has built and supported a series of front rank accelerator systems aimed principally at research in particle physics.

COMPASS Common Muon and Proton Apparatus for Structure and Spectroscopy Experiment at CERN in which hadron structure and hadron spectroscopy are studied with high-intensity muon and hadron beams.

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CSR

Comprehensive Spending Review Process by which the UK Treasury sets firm limits to the expenditure of government departments and defines what the public can expect from this expenditure.

DESY

Deutches Elektronen-Synchrotron (Hamburg, Germany) DESY is a national research facility in Germany. It operates particle accelerators for a variety of purposes including particle and hadron physics.

ELSA

Elektronen-Stretcher-Anlage (Bonn, Germany) Electron accelerator and stretcher ring that provides beams of polarised or unpolarised electrons of a few nA at variable energies up to 3.5 GeV.

EPSRC

Engineering and Physical Sciences Research Council One of the UK’s research councils. As the name suggests, it funds research in the physical sciences and engineering. It has responsibility for funding applications of nuclear science, particularly the application of nuclear fission and fusion.

ESFRI

European Strategy Forum on Research Infrastructures Strategic instrument to develop the scientific integration of Europe and to strengthen its international outreach.

EURISOL

European Isotope Separation On-Line Next-generation accelerator system for radioactive ions based on isotope separation online. Note: at time of writing, it is not yet funded.

FAIR

Facility for Antiproton and Ion Research (Darmstadt, Germany) Next-generation facility based on current accelerator systems at GSI. It will generate radioactive beams using high-energy fragmentation and fission.

FRIB

Facility for Rare Isotope Beams (Michigan, USA) A new national user facility for nuclear science. It will provide beams of rare isotopes.

G7

Group of 7 Nations Seven richest industrialised countries: France, Germany, Italy, Japan, the UK, the USA and Canada.

GANIL

Grand Accélérateur National d’Ions Lourds (Caen, France) Large Heavy-Ion National Accelerator. A Review

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Gesellschaft fur Schwerionenforschung (Darmstadt, Germany) German national laboratory devoted to nuclear science. It will be the site of FAIR, which will make use of its infrastructure.

HERMES

An experiment located at DESY aimed at determining the spin structure of the nucleon.

ISOLDE

Isotope Separator On-Line Detector (CERN) Online isotope separator facility aimed at producing a wide variety of beams of radioactive ion species. The beams are used in many branches of science. It has a post-accelerator currently being upgraded to 5.5 MeV per nucleon.

JLab

Jefferson Laboratory (Virginia, USA) The Thomas Jefferson National Accelerator Facility, housing the Continuous Electron Beam Accelerator.

MAMI

Mainz Microtron (Mainz, Germany) Nuclear physics laboratory at the University of Mainz. It currently consists of a harmonic doublesided microtron coupled to a cascade of three racetrack microtrons. It can deliver polarised (up to 80%) and unpolarised electron beams at energies up to 1.56 GeV.

NPAP

Nuclear Physics Advisory Panel STFC panel providing advice on nuclear physics to the Science Board of the STFC.

NuPECC

Nuclear Physics in Europe Collaboration Committee An expert panel of the European Science Foundation.

NuSTAR

Nuclear Structure Astrophysics and Reactions Scientific collaboration aimed at building apparatus to exploit radioactive beams at FAIR to study nuclear structure, reactions and astrophysics.

QCD

Quantum chromodynamics A theory of the strong interaction. It is a non-abelian gauge theory consisting of a “colour” field mediated by gluons, the exchange particles. It is part of the Standard Model of particle physics.

QGP

Quark–gluon plasma A plasma of asymptotically free quarks and gluons thought to exist at very high temperature or density. A primordial soup of this type is believed to have existed in the early universe.

RCUK

Research Councils UK A partnership of the UK’s seven research councils. The term is used when they engage in joint activities.

RHIC

Relativistic Heavy Ion Collider A high-energy intersecting storage-ring accelerator for heavy ions sited at Brookhaven National Laboratory, USA. RHIC provides 100 GeV per nucleon beams of heavy ions and 250 GeV proton beams.

RIKEN

Rikagaku Kenkyusho The Institute of Physical and Chemical Research, a major Japanese laboratory providing among other things radioactive ion beams from a fragmentation facility.

SPIRAL

Systeme de Production d’Ions Radioactifs Accelere en Ligne Isotope separation online facility producing radioactive ion beams at GANIL. SPIRAL II is currently under construction and will provide greatly enhanced beam intensities for many chemical species.

STFC

Science and Technology Facilities Council UK research council charged with funding particle physics, nuclear physics and astronomy. STFC operates large-scale facilities in the UK and is responsible for UK membership in large-scale facilities abroad, such as CERN.

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Appendix 3: Nuclear physics PhD skills set The panel considered what skills a student might be expected to acquire in undertaking a PhD in nuclear physics in the UK. In the panel’s view the skills listed below are characteristic of those acquired by such graduates. Scientific background: Advanced physics principles: nuclear physics, radioactivity, interaction of radiation with matter, detector operation, nuclear processes and reactions, quantum mechanics, many-body physics and effective field theories. Advanced mathematical techniques: Statistical analysis, mathematical modelling, numerical methods, programming skills and software development, debugging and testing of computer codes, advanced calculus and algebraic methods. Technical skills: Design, construction, testing, maintenance and use of advanced instrumentation, including: radioactive sources, handling and safety issues; radiation detectors, scintillators, semiconductors, ion chambers and novel detections/sensors; ion beams, optics and sources; vacuum systems/gas handling; electrical/ electronic systems; signal processing, electronics, control and data acquisition systems; mechanical design; lasers and laser techniques. Technical problem solving.

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Research skills: Well developed imagination, creativity and critical thinking in developing research methods and techniques. Inquiring, questioning and innovative attitude. High levels of expertise in experimental design. Critical application of logic and reasoning in scientific argument or to reach conclusions. Project management and planning. Computation and analysis skills: Programming and code development. Numerical analysis, often with large data sets. Statistical analysis. Advanced computation, modelling and simulation, particularly radiation transport in matter. Interpretation of results of numerical analysis. Critical evaluation. Other personal skills: Technical writing. Public speaking and presentation. Time management and organisation. Information retrieval. Independent working. Teamwork and effective collaboration, both local and distributed, often multinational.

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For further information contact: Tajinder Panesor 76 Portland Place, London W1B 1NT Tel +44 (0)20 7470 4800, Fax +44 (0)20 7470 4848 E-mail [email protected] www.iop.org Charity registration number 293851 Scottish Charity Register number SC040092 The report is available to download from our website and if you require an alternative format please contact us to discuss your requirements. The RNIB clear print guidelines have been considered in the production of this document. Clear print is a design approach that considers the requirements of people with visual impairments. For more information, visit www.rnib.org.uk.

This publication was produced by IOP using responsibly sourced materials.