A Journey Through ISIS a Behind the Scenes Look at Using Neutrons and Muons for Cutting-Edge Science a Journey Through ISIS
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A journey through ISIS A behind the scenes look at using neutrons and muons for cutting-edge science A journey through ISIS Contents Welcome to the journey! The start of the journey Page ISIS at the STFC Rutherford Appleton 1 Neutrons and muons for science ........................................ 2 Laboratory in Oxfordshire, UK, provides unique sources of both The journey’s aim pulsed neutrons and muons for 2 Exploring drug delivery ........................................................ 6 exploring the properties of matter by Different routes to take measuring the locations of atoms and the forces between them. 3 The ISIS instrument suite ..................................................... 8 Permission to travel ISIS employs more than 300 highly- 4 Submitting a proposal for ISIS beam-time ...................... 12 qualified scientists, technicians, engineers and administrative staff, Getting ready to go who have unique skills. Their work 5 Preparing for the experiment ............................................ 14 ensures that the science carried out by research groups is first-class. ISIS Support along the way teams looking after the accelerator, Operating ISIS ...................................................................... 18 6 beamlines, instruments and computers The heart of the journey work around the clock to ensure that 7 Running the experiment ..................................................... 22 experiments are successful. At journey’s end We will follow the journey that one 8 After the experiment .......................................................... 26 research group makes as they use ISIS to further their research goals – from Helping others to travel the initial idea for an experiment, 9 Training for ISIS users and staff ........................................ 28 through submitting a proposal, to ISIS Scientists ....................................................................... 30 carrying out the experiment and analysing the results. Along this Further information ............................................................ 32 journey, we go behind the scenes to meet the people who work at ISIS and learn about how the facility operates. 1 e start of the jo A journey through ISIS Th urney… Extracted proton beam WISH 800 MeV SYNCHROTRON offSPEC INTER Neutrons and muons polREF SANS2d for science MICE Extracted proton beam NIMROD – HRPD 70 MeV H Linac LET ISIS is a world-leading research centre serving the UK Neutron techniques and international scientific community have distinct EC Muon Facility benefits: MuSR HiFi • Neutron studies can Research carried out at the science, environmental and RIKEN Muon Facility ENGIN-X What do neutrons tell us? EMU range from the distances microscopic scale – whether into the geological sciences, and increasingly ARGUS between atoms natural world or manmade materials the life sciences. Neutrons are one of the two (0.1 nanometres) to those – has been responsible for many of constituents, along with protons, of TOSCA associated with the the major improvements in our The UK has a major facility, ISIS – HET HiPr atomic nuclei. Fired into samples, INES GEM structures of large quality of life. based at the Rutherford Appleton IRIS they can tell us where atoms are and POLARIS molecular arrays (over Laboratory near Oxford and operated how they are moving deep inside MARI OSIRIS 500 nanometres). Sample objects can now be studied by the Science and Technology materials. LOQ with various kinds of radiation to Facilities Council – which provides MERLIN • Neutrons are penetrating CRISP SXD reveal the locations of atoms and neutron beams for research. This atom’s-eye view helps us to SURF enough to reach deep the forces between them at the Academic research groups from explain why substances have the VESUVIO inside a sample. ROTAX atomic and molecular levels. An across the UK, and further afield, can MAPS properties they do – for example, PRISMA • They are non-destructive increasingly important approach is apply for ‘beamtime’ at ISIS. how they conduct electricity, why SANDALS so can be used on the use of beams of electrically they have particular magnetic delicate biological neutral subatomic particles – ISIS experiments provide detailed properties, or how tough they are – samples. neutrons – which can scatter off insights into the arrangement and and so can help us make new materials in a way that gives just behaviour of atoms and molecules in substances that are useful in • Neutrons are very such information. Neutron scattering a material, which are not obtainable everyday applications. sensitive to light atoms techniques are now applied across by other methods. such as hydrogen. many scientific disciplines – physics, When neutrons interact with the • Atoms such as hydrogen, chemistry, engineering, materials atoms in a solid or liquid, they in a selected sample scatter off the nuclei in a component, can be characteristic manner that depends substituted by a variant on the atomic positions. The angles with a different number at which the neutrons emerge from of neutrons in the nucleus the sample tell us the distances – an isotope – which between the atoms. Any changes in scatters differently and the neutron energies as they pass so picks out that through the samples also reveal the component. motions of atoms and molecules. • The structure of surfaces and interfaces can be revealed by bouncing neutrons off them – the technique of neutron reflectometry. • Because neutrons have a magnetic moment, they are sensitive to the often subtle electronic structures of magnetic and superconducting materials. The newly-built ISIS Second Target Station The ISIS synchrotron 2 accelerator 3 start of the The journey A journey through ISIS Neutrons and muons The ISIS pulsed muon source Muons offer an ingenious way of exploring atomic-scale structure in solids and liquids, for science providing complementary information to that gleaned from neutron experiments Muons are produced from a thin them once inside affects their graphite target when the spins in a way that provides energetic proton beam from the atomic-level information. Muons Making a neutron beam A wide range of A bright future for ISIS ISIS accelerator passes through. can be used to study a broad experiments and They survive for only two range of materials, including millionths of a second but that is magnetic and superconducting Neutrons can be released by firing instruments A second target for neutron bursts of accelerated protons at a production – Target Station 2 – with a long enough to carry out samples, molecular systems and metal target, knocking out, or suite of new beamlines and experiments with them. The chemical reactions, Once the neutrons escape from the spallating, neutrons from the target’s instruments, will increase capacity muon beams are steered to semiconductors, battery target, they are slowed down nuclei. This spallation neutron and widen research potential at ISIS. seven experimental areas, three materials, organic materials used (a process called moderation) and approach has been extremely Further novel improvements are being in the ISIS European muon in displays – to name but a few. directed along beamlines to some successful. It is being taken up made to increase the intensity of the facility and four in the Japanese- 20 instruments where experiments elsewhere in the world and will neutron pulses, so ISIS users can look run RIKEN-RAL facility. The RIKEN-RAL facility also take place. carries out studies including Muon beamlines of certainly be the basis of any future forward to the prospect of carrying the ISIS European international neutron facility. out even more exciting science. The main technique employed muon-catalysed fusion – an muon facility Each instrument is designed for a using muons relies on the fact exotic mode of nuclear fusion specific type of experiment. For …and muons that they have a spin and so which happens at low example, large polymer networks are behave like minute magnets. temperatures, though not yet studied using an instrument which Muons readily implant efficient enough to provide As well as producing neutrons, the measures neutron scattering at small themselves in samples, and the energy – and other atomic and proton pulses are also directed at a angles (small angle neutron magnetic environment around nuclear investigations. target designed to produce muons, scattering, SANS). which are another useful probe of the properties of materials (see opposite). The basic requirement for producing neutrons and muons is a powerful accelerator system to generate an energetic proton beam. ISIS has several accelerator stages, culminating in the circular synchrotron accelerator 50 metres across. This produces protons travelling at 84 per cent of the speed Adrian Hillier of light. inspects one of the muon spectrometers ISIS science covers a wide range of length scales – from the distances between atoms in crystals to large molecular structures and magnetic domains Neutron experiments can be used to study: • Advanced materials such as • Compounds with exotic • Proteins, DNA and cell catalysts, hydrogen-storage magnetic and electronic membranes materials, battery materials properties, including high- • Complex biomedical materials temperature superconductors • Nano-materials and structures • Disordered materials and liquids such as magnetic thin films • Engineering stresses and strains used in computer applications in components and welds • Rocks and minerals – terrestrial and planetary