The proposed knowledge exchange is to transfer R&D into automatically joining by welding ultra thin wall advanced aerospace alloy small diameter tubing. Sourced directly from STFC funded research into low mass cooling systems; the technique, processes and knowledge will enhance modern aerospace and hybrid vehicle turbine manufacture by facilitating the removal of heavy fuel and cooling line connectors currently adopted by manufacturers. Reliable high strength welded joints are only achievable on thin wall aerospace alloy tubes through automated processes, all currently very costly and do not allow for simple in-situ installation of components. Reduction in the use of connectors in turn will allow for more compact turbine design and higher reliability. Savings made by the enhanced reliability of light weight connector less fuel and cooling systems will allow the efficiency gains sought after by gas turbine market consumers.

"What is the Universe made of, and why?" Sheffield's HEP programme aims to address this fundamental question. There are two problems here: about 5/6 of the matter in the Universe seems to be an as yet undiscovered particle (dark matter), and the remaining 1/6 is all matter - not the 50:50 matter-antimatter mix we make in laboratories. We search for the dark matter particle in two ways: at the energy frontier, by seeking to detect new particles created by the high-energy proton-proton collisions of the LHC at CERN, and in direct searches, attempting to observe these particles in the Galaxy itself. The theory of supersymmetry, which predicts a whole set of particles related to, but more massive than, the known particles of the Standard Model (SM), offers a candidate dark matter particle. If supersymmetric particles can be made at the LHC, they should be detected in ATLAS. Our programme searches specifically for new Higgs bosons and for particles related to the SM quarks and gluons. At ATLAS, we also study SM processes involving the force carriers of the weak interaction, probing our understanding of the SM. Looking to the future, we are contributing essential work to the upgrade of the ATLAS experiment required to take full advantage of higher event rates in future running of the LHC. Most of the matter in our Galaxy is dark matter. In the LZ experiment, we search for evidence of dark matter colliding with Xe atoms in the experiment and causing them to recoil. This experiment will be the most sensitive dark matter detector ever constructed. Understanding possible background - non-dark-matter - events is critical to this, and we have world leading expertise in this field. In addition, we are leading the development of directional dark matter detectors, which will be vital in proving that any candidate signal really does come from the Galaxy and not the Earth. We are also the only UK group involved in the search for axions: another possible type of dark matter particle which cannot be detected at the LHC or in standard dark matter experiments. Why is the matter in the Universe all matter, not antimatter? The answer to this question must lie in subtle differences between particles and antiparticles, an effect called CP violation. The CP violating effects so far observed are not nearly large enough to create the Universe we see. The most likely source for more CP violation is in the interactions of neutrinos. A key observation is that neutrinos have mass, and that different types of neutrinos can interchange their identities in flight. The T2K experiment has made measurements of this, and has detected tantalising hints of CP violation. We plan to build on this work, both in running experiments (T2K and SBND) and in designing the next generation of neutrino experiments which will have much greater sensitivity. We have developed tools to assist the neutrino community in comparing results and improving our understanding of how neutrinos interact. Our access to Boulby Mine provides an invaluable low-background laboratory for testing materials and detector prototypes. Last but not least, we seek to apply HEP technology to industry and to solving global problems. We are using techniques developed for ATLAS to contribute to the development of robotics and to deal with highly radioactive environments such as Chernobyl. We are designing muon detectors to search for nuclear contraband and monitor volcanoes. Our signal processing techniques are being applied to improving medical imaging for heart patients. Our expertise in water Cherenkov neutrino detection is being exploited in an experiment designed to monitor compliance with nuclear non-proliferation treaties. All of this work builds on our STFC core programme to benefit the wider world.

It is an exceptional time for discoveries in particle physics and particle astrophysics and the research we wish to conduct in this STFC consolidated grant programme at Sheffield is at the heart of this action. Foremost recently has been the discovery by ATLAS of a Higgs boson particle. Members of the group led and helped to develop the key 4-lepton analysis upon which the discovery was based. We will now use our expertise to measure carefully the properties of the new particle to establish whether it is the Higgs boson predicted by theory, or something else. We will also search for squark and gluino particles predicted by supersymmetry theory, which will be the main target of the next, higher energy, run of the LHC. Preparing for the future, we will expand our role in the ATLAS upgrade programme to build key components of a new ATLAS tracker. Our involvement in the T2K experiment in Japan also greatly benefited from confirmation of a non-zero third neutrino mixing angle, a result fundamental to our understanding of the neutrino. The group's respected work in neutrino analyses for T2K, particularly of so-called charge current and neutral current events, will continue along with international responsibilities for data management and for the critical light injection calibration system. However, bolstered by the exciting new results we will now also accelerate participation in next generation long baseline neutrino experiment for CP violation aimed to unravel the mystery of antimatter in the Universe, notably using LBNE/F in the US and Hyper-K in Japan. For these our particular focus will be on detector construction. For the precursor LAr1-ND experiment at Fermilab we plan to construct the central Anode Plane Array for the detector, while working also on our pioneering liquid argon R&D. We will also establish novel detector prototypes at the new CERN-based neutrino platform and for LBNE/F itself. Closely related here will be work on the MICE experiment towards a potential future neutrino factory, plus related R&D on high power particle beam targets for future neutrino beams and experiments. For particle astrophysics we plan to expand work on gravitation waves, through specialist noise analysis for Advanced Ligo, and develop new effort on dark matter, thought to comprise 90% of the Universe. There is strong motivation here because the US LUX experiment recently produced a step-change in sensitivity to dark matter particles. We will complete leading analysis for the EDELWEISS experiment and then lead key simulations for the upcoming LZ experiment in the US. Following our pioneering work on detectors with sensitivity to galactic signatures, the group will also lead analysis and construction tasks for the DRIFT direction sensitive experiment at Boulby and the new DM-ICE250 NaI experiment, which US collaborators recently agreed will be hosted at Boubly. DM-ICE will seek a new annual modulation signal for dark matter. These experiments are all searching WIMP particles, but we will also expand study of axions as a potential alternative. Meanwhile, our generic detector R&D and knowledge exchange programme is vital to underpinning the group's expertise and skills-base. It benefits from our historic links to the Boulby deep underground science laboratory but critically now involves multiple industrial and non-STFC projects. Noteworthy aims now will be to complete our DECC-funded programme on muon tomography for climate change, develop new instrumentation for radon assay, spin-out work on novel motor control electronics via a new patent and continue development of novel welding technology. It is interesting that our long-standing efforts to develop liquid argon technology for neutrino physics are also relevant to medical imaging requirements. We plan to complete a new prototype instrument, building on a recent MRC award. This all reflects the group's commitment to contributing to societal and impact agendas.

Brazing is an important process for joining materials. It is quick and permits high strength, and is unique among high-temperature permanent joining methods in leaving the materials being joined largely unchanged; hence it can make complex joints and join dissimilar and difficult to weld materials (e.g. metals to ceramics and high Al/Ti content nickel superalloys respectively). It works by having a specific alloy, called a Brazing Filler Metal (BFM), introduced between the parts to be joined. Thermal treatment of the assembly is used to melt and solidify the BFM, forming a bond. These BFMs are designed specifically for different types of bonding situation, and can have many different compositions. Brazing is a key technology for many advanced applications, including the aerospace and nuclear sectors, but it has limitations. As the service requirements become more demanding, and base metals are refined, new BFMs must be developed. Some specific problems facing brazing technology today include: 1) Widening the spectrum of materials that can be joined (including higher temperature materials, bonding metals to ceramics, and also lower process temperatures for materials that cannot survive those of existing brazing alloys; functional ceramics and high strength 7000 series aluminium alloys, for example), would open up a whole host of novel technologies, using both existing and advanced materials in new ways 2) High temperature brazing uses additions such as boron or silicon to suppress the BFM melting point. They do this well, but also introduce brittle intermetallic phases in the joint region, limiting mechanical performance. 3) In practice, the parameters for brazing are determined on an application-specific basis, by experimental trial and error. Greater fundamental understanding of the brazing process will render this more efficient, permitting the brazing conditions to be designed. This project builds the understanding to address such challenges. A new type of alloy, High Entropy Alloys (HEAs) has recently come to the fore for alloy design. In these alloys, similar amounts of many elements are combined, rather than the typical approach of main solvent element with small additions of other elements to adjust the properties. Some HEAs have reported properties desirable for BFMs; e.g. the ability to add large amounts of elements to control melting point or wetting and flow behaviour without inducing brittle phases, and the multicomponent nature could mediate the transition in a joint between dissimilar materials. However, the physical metallurgy of HEAs is still relatively poorly understood, and their use in brazing has only been explored to a very limited extent. In this work we are investigating systematically the design, understanding and use of HEAs as BFMs. This both adds to our fundamental understanding of this intriguing new class of alloys, and provides the knowledge and skills to permit the design of new products for industry. The data and computer models of the brazing process we will generate give the design methods and data for the development of brazing parameters, which is currently done on a case-by-case basis. The project brings together the UK academic and industrial community on brazing for the first time, and will act as a focus for brazing interest. Aided by our industrial partners we will demonstrate the outcome of this work by two example case studies of alloy development: I) Reduced cost BFM for aero engines; current alloys contain significant amounts of Au and so a noble metal-free BFM, with appropriate performance, would reduce costs. II) Fusion BFM; to build advanced fusion reactor designs, it is necessary to join tungsten blocks on the reactor interior to copper pipes for coolant. This is currently done with BFMs with melting points <325degC; this limits operating temperatures. A new BFM would improve the performance and give more design flexibility for fusion reactor components.

We are living in an exceptional age for discoveries in particle physics and particle astrophysics with potential for producing step changes in understanding of the composition of matter and the structure of the Universe. The research we plan with this consolidated grant in particle physics and particle astrophysics at Sheffield is at the core of these discoveries. Firstly, we appear to be near answering the fundamental question of what gives particles mass. In this field Sheffield will continue to play a leading role in the ATLAS experiment that now looks to be on the verge of solving the mystery by detecting the famous Higgs Boson. Our ATLAS work, where we are currently the only UK group heavily involved in the flagship 4-lepton channel Higgs search, will aim to confirm the first evidence for excess reported in Dec. 2011. Simultaneously work will continue in the equally fundamental hunt to find supersymmetric particles and on radiation modeling and detector tests for the ATLAS upgrade anticipated as the next experiment. We currently provide the UK spokesman for ATLAS. A second recent major advance, made by the T2K experiment in 2011, reports evidence for a non-zero third neutrino mixing angle. This potentially unlocks progress to experiments in so-called charge-parity (CP) violation to answer the mystery of why the Universe contains matter and virtually no anti-matter. Our T2K and neutrino group will focus on contributing further analysis to confirm the new results but also, using our membership of the LBNO and LBNE collaborations, progress key new detector technology towards a next generation long baseline neutrino experiment to see CP violation. For this our focus will be with liquid argon technology, our pioneering work on electroluminescence light readout for that, and our simulation work on backgrounds from muons. The latter is key also to our on-going work towards an experiment to see if the proton decays, an issue at the core of understanding Grand Unified Theories of physics. Closely related and vital for our neutrino programme is continued participation in SNO+, aimed at understanding solar neutrinos, and the MICE experiment with its related R&D on high power particle beam targets for future neutrino beams. Technological developments recently led to significant improvement in sensitivity of detectors to WIMP dark matter with key contributions from the Sheffield group towards EDELWEISS and DRIFT. Exploiting our leadership in background mitigation strategy, calibration and data analysis, our future work will concentrate on EDELWEISS operation and data analysis, as well as on developments towards ton-scale cryogenic experiment EURECA. The group is also uniquely well positioned to contribute through new work aiming to see, or exclude, a definitive galactic signature for the claimed low mass WIMP events. Our pioneering work on directional WIMP detectors will see a new experiment installed at the UK's Boulby underground site, DRIFTIIe, while our continued analysis of data from DM-ICE17 at the Antarctic South Pole, for which we supplied the NaI detectors, will seek an annual modulation galactic signature and inform design of a new experiment there planned for 2013. Our generic detector R&D is vital to underpinning the group, closely related to a vigorous knowledge exchange programme that now includes funded projects involving 15 different companies. Highlight activity here will include development of particle tracking technology in liquid argon relevant to neutrino physics and astrophysics, new gas-based directional neutron programmes with relevance for homeland security, and new muon veto R&D. The latter links to our KE programme on CO2 underground storage technology. We plan first deployment of test detectors at 760m depth by 2013. This is part of the group's contribution to key social agendas in climate change and crime prevention.