Stratocumulus clouds are common over S England occurring about 25% of the time. The clouds are rather thin with clear sky above, so if they break up then an overcast day is suddenly transformed into a clear sunny day; alternatively they can rapidly develop and spread over the sky changing a sunny day into a gloomy overcast one. Their formation, persistence and dispersion are surprisingly difficult to forecast. On a global scale they form widespread cloud sheets over the cold ocean water, for example, off the coast of California, Peru and Namibia. These cloud sheets have an important effect on the climate of the earth, as they reflect the sunlight straight back to space rather, and so their presence has an overall cooling effect. It is important to represent any changes in the future extent of these clouds sheets correctly if we are to have accurate predictions of future global warming. The models used for weather forecasting and for predicting future climate change split the atmosphere into large grid boxes which are typically up to 500m deep and tens or hundreds of km across, with only two numbers used to describe the cloud in each box (e.g the amount of cloud and the mass of cloud water). Stratocumulus clouds are difficult to forecast because they are often only 100m deep and can block out the sun, but are not deep enough to fill a model grid box. In a layer about 1km deep close to the surface of the earth the air is being continuously mixed and stirred in the vertical and the stratocumulus clouds form at the top of this mixed 'boundary' layer. The existence of the clouds is governed by a delicate balance between the moisture from the surface of the ground or the ocean which feeds the clouds, and the mixing of dry air above the boundary layer tending to disperse them. Another important mechanism is the formation of drizzle in the clouds which tends to remove the moisture and so disperse the clouds. The cloud droplets themselves are formed on small dust particles, so the properties of the clouds are dependent upon the level of dust or pollution in the air. The purpose of this proposal is to make detailed observations of the vertical structure of stratocumulus clouds over a period of several years with lidars and radars on the ground. A radar sends out short pulses of radio waves; the cloud scatters some of these waves back to the radar, and by timing how long the echo takes to be returned and by measuring its strength we can calculate the height of the cloud and how much water it contains and identify if the cloud is producing drizzle. The vertical velocity of the cloud and drizzle drops can be inferred from 'Doppler shift', the change in radio frequency of the reflected wave. A lidar works on the same principle but uses light; we have lidars that sense the light reflected of dust particles in the air so we see how many of these particles are present, and then sense the vertical movement of the air from the Doppler shift of the lidar echoes. Other lidars can detect how much moisture is in the air and so by combining these observations we can measure the vertical movement of moisture into the clouds, the drizzle falling out of the clouds, the mixing of dry air at cloud top and see how these relate to the evolution of the cloud and its persistence or break up. Once we understand these processes we can try to improve the forecasts. To this end we are collaborating with the Meteorological Office and the European Centre for Medium Range Weather Forecasting, so we can test out improved means of representing these stratocumulus clouds in their operational forecast models. The aim is to produce models which provide better weather forecasts of whether a day is to be cloudy or sunny. In addition, a better representation of the extensive regions of stratocumulus over the cold oceans will increase our confidence in the accuracy of the predictions of global warnings.

Ionic liquids (ILs), with their unique combination of properties and wealth of potential applications, have captured the imagination of a large community of scientists in recent years. Fundamental studies on ILs have led to breakthroughs in our understanding and have enabled the development of ILs that are promising candidates for use in areas such as catalysis, carbon-capture and storage (CCS), biomass processing, as electrolytes in batteries, supercapacitors and dye-sensitised solar cells and more. This project aims to develop and utilise a wide range of experimental and computational methodologies to investigate the surface, and bulk, structure of IL mixtures that are currently poorly understood and consequently underutilised. We previously developed a novel technique that can probe liquid interfaces with direct chemical specificity, Reactive-Atom Scattering - Laser-Induced Fluorescence (RAS-LIF), and used it to detect H (or D)-containing functional groups at IL interfaces. We will extend its applicability to new chemical functionalities, in particular fluorinated species, by using high-energy Al-atoms as reactive probes of fluorinated functionality (on both cations and anions) at IL surfaces. This will be complemented by new capabilities for studying liquid surfaces by X-ray and neutron reflectivity under catalytically relevant conditions, and by bulk structure/property studies. The detailed understanding developed will lead to structure-property relationships in IL mixture systems that will be used in the final stages of the project in supported IL phase (SILP) catalysis and will support the deployment of new and bespoke functional ILs for catalysis in SILP systems. This ambitious project aims to cover the whole pipeline of IL development from preparation, to structural understanding, and then to industrially relevant applications.

The determination of chemical structure is vital in understanding the efficacy of medicines and materials and consequently underlies innovation. The equilibrium positions of atomic nuclei can be routinely determined by the technique of X-ray diffraction. However, this provides only part of the information required by a chemist. In order to develop new medicines and materials it is necessary to understand bonding character and reactivity; these are determined by the energies and spatial distributions of electrons, the so-called "electronic structure". In order to investigate electronic structure, including the changes it undergoes during a chemical reaction, new probes are required. Whereas photoelectron spectroscopy (the emission of electrons caused by the interaction of molecules with UV light) has long been known to be sensitive to electronic structure, far more intimate details can be obtained by the measurement and analysis of the angles through which the photoelectrons are emitted. The information content of these angular measurements dramatically improves if measurements can be made relative to bonds in individual molecules. This is challenging because free molecules rotate, and measurements are therefore averaged over all the possible molecular orientations. Furthermore, a full characterization requires measurements to be made over a wide energy range. The combination of these requirements has severely limited the scope of most experiments to date. The recent parallel developments of (a) techniques to align molecules in space, and (b) technologies that have enabled the development of a new generation of high energy light sources, is set to revolutionize capabilities, bringing the exciting prospect of observing how electronic structure evolves in time. Here, we propose a series of novel experiments that will combine and exploit these ideas and technologies to develop sensitive probes of evolving electronic structure, and protocols for their implementation and interpretation, facilitating uptake by other groups. The proposed work is timely because of the recent technological developments and the research team is well-placed to advance the state-of-the-art through their expertise in the measurement and interpretation of photoelectron angular distributions and in light source development.

Fusion energy is likely to become a major contributor to world electricity generation capacity. The extent to which this will occur will become clear over the next 10-15 years with the construction and operation of ITER (the second largest international science project after the International Space Station). In parallel, the HiPER proposal, for example, will explore the potential for inertial confinement fusion. In this timescale the UK must develop a cadre of trained personnel who have the ability to contribute to the decisions the UK will have to make and, if the decision is to take this route, to train the generation of scientists and engineers who will license and build fusion power plants in the UK. In the nearer term, JET (sited at Culham) is undergoing a ~100M upgrade programme and there are also advanced plans for the UK's domestic tokamak, MAST, to be significantly upgraded. With inertial fusion, the Orion laser facility is just coming on line at AWE Aldermaston. These offer exciting opportunities for young scientists: a fact reflected by the high popularity of fusion amongst students. For the UK to maximise the benefits from these facilities and be in a position to contribute to and exploit the spin-offs of fusion science and technology, it is essential that there is a coordinated training programme to provide a critical mass of manpower, the quality of which is recognised internationally. There is no such programme in the UK at present and the core aim of this proposal is to take the first steps towards addressing this need. Specifically it will establish some of the infrastructure and the collaborative network to prepare the way for a full Doctoral Training Centre in the future.To address the breadth of research needs for fusion as it enters the ITER era, a strategic objective of the proposed Fusion Training Network is to initiate a programme of cross-disciplinary, multi-institutional, collaborative doctoral training, including strong support from UKAEA Culham and the Central Laser Facility. Students will register with one of the four partner universities. They will receive 6 months of formal courses in a broad range of fusion topics from plasma physics to fusion technology, gaining an appreciation of both experimental and computational techniques employed in fusion research. Students will also identify opportunities for collaboration with each other during this time; opportunities that they will exploit during their reseach projects. Thus, a student working on the plasma physics associated with plasma-surface interactions at Liverpool might work in collaboration with a materials scientist at Manchester designing the tokamak exhaust components. Another example is that an inertial fusion specialist measuring opacities at York might work with a spectroscopy specialist at Durham working on tokamaks to understand how the opacity of the plasma edge region affects interpretation of spectroscopic plasma diagnostics. Students will benefit from access to a wider range of experience than a single institute can offer. They learn how to work collaboratively and broaden their experiences, gaining appreciation of other fields.The training network will combine basic science, technology and engineering to create the foundations for a multi-disciplinary training and research environment that is not currently achievable at UK national laboratories or at a single university. The main objective is to establish the environment and procedures to train cohorts of highly skilled researchers who will ultimately lead research programmes for the UK at an international level. Furthermore, although fusion is the main drive for the training network, the ultimate goal is to produce students with a breadth of expertise that will qualify them to take posts in other areas of strategic importance, such as the fission industry and the rapidly growing industry associated with technological plasmas.

The terahertz (THz) region of the electromagnetic spectrum spans the frequency range between microwaves and the mid-infrared. Historically, this is the most illusive and least-explored region of the spectrum, predominantly owing to the lack of suitable laboratory sources of THz frequency radiation, particularly high-power, compact, room-temperature solid-state devices. Nevertheless, over the past decade, THz frequency radiation has attracted much interest for the development of new imaging and spectroscopy technologies, owing to its ability to discriminate samples chemically, to identify changes in crystalline structure, and to penetrate dry materials enabling sub-surface or concealed sample investigation. One of the most significant recent developments within the field of THz photonics has been the THz quantum cascade laser (TQCL). These high-power compact semiconductor sources have opened up a host of new opportunities in the field of THz photonics and have attracted significant research interest world-wide. However, there is the need to develop techniques for measurement of the phase of the radiation field emitted from TQCLs, thereby providing a complementary technology to currently established incoherent detection schemes. Furthermore, there is a need to explore fully the advances that can be made through control and manipulation of the phase of the THz field emitted by TQCLs. My vision is to initiate a range of research programmes with the aim of probing, manipulating and utilising the coherent nature of TQCL radiation. This will lay the foundations for a wealth of research opportunities in THz photonics, as well as facilitating the exploitation of THz technology for fundamental science and also for real-world applications. I will develop both optical and electronic techniques for coherent detection/measurement of the field emitted by TQCLs. One means of achieving optical coherent detection is through the up-conversion of the phase and amplitude of the THz field into the near-infrared band with an electro-optic (EO) crystal. This approach will also allow the large field amplitudes and narrow line-widths of TQCLs to be exploited, enabling QCL radiation to be sampled using a broad-area EO crystal and a standard optical CCD. This will open up a significant range of opportunities for exploiting well developed visible/near infrared detector and CCD technologies within THz science. In parallel, I will develop coherent detection techniques by down-conversion of the THz field to radio frequencies. I will accomplish this through heterodyne phase-locking the fields from two TQCLs using a Schottky diode. I will investigate coherent detection using self-mixing in TQCLs. This method relies on sensing junction voltage perturbations induced by feedback of the radiation field into the TQCL cavity, enabling coherent detection of the field using a single TQCL device as both source and detector. Using this approach, linewidth narrowing in TQCLs will be investigated, as well as techniques for three-dimensional 'detector-less' imaging and tomography. I will also establish a programme concentrating on the radio-frequency control and manipulation of the THz field through the use of dynamic and static gratings, generated and controlled via the interaction of surface acoustic waves (SAWs) with TQCL devices. This approach will be used to provide a non-contact means to apply a potential modulation to TQCL devices, thereby providing a distributed feedback mechanism for the THz wave. As part of this I will develop TQCLs with reduced active regions thicknesses and TQCL mesa structures. The combination of all these technologies will be combined to demonstrate the first 2D phase-sensitive THz tomography system using QCLs, the first full-field imaging system combining TQCLs and commercial CCD technology, and high-resolution THz gas spectroscopy.