Particle and Nuclear Physics Applied Systems - A pilot scheme for knowledge exchange

Grants awarded

Professor R Barlow, University of Manchester, ‘Using Thorium as fuel in conventional Reactors’, funds awarded £424,447. Start date 1 July 2009 until 30 June 2011

Thorium could provide an ideal source of fuel for nuclear reactors. More abundant than Uranium, Thorium-232 is a fertile isotope which can absorb a neutron to produce Uranium-233. Uranium-233 is a fissile isotope which can power reactors. It produces much less long-lived waste than the Uranium/Plutonium process, and is also highly unsuitable for military purposes by 'rogue states'.

Some Thorium reactors have been designed, and a few have been built. These have provided the extra neutrons to accomplish the initial Thorium - Uranium production by using an external accelerator together with the reactor, or by mixing some U-235 or Plutonium with the Thorium. The first option is expensive, the second means that long-lived waste is still produced.

We propose to accomplish the conversion of Thorium to Uranium by first irradiating the Thorium with neutrons from a spallation source. This would produce enough Uranium-233 to make such fuel rods net producers of neutrons, when they are used to fuel a conventional reactor. The project will model irradiation of a Thorium fuel rod by spallation neutrons and its subsequent performance in a power reactor, through its complete life cycle. It also involves measuring some of the extra cross sections we still need to know, and will study the behaviour of Thorium, and Thorium Oxide, under high neutron doses, to verify the mechanical design of the fuel rods.

Our aim is to produce a design for Thorium loaded fuel rods and a procedure for irradiating them with neutrons such that they can be introduced into existing nuclear power stations in the UK and worldwide.

Dr A Boston, University of Liverpool, ‘ProSPECTus: Next generation single photon emission computed tomography’, funds awarded £979,800. 1 August 2009 until 31 July 2011.

The ProSPECTus project will develop the demonstrator of next generation Single Photon Emission Computed Tomography (SPECT) imaging system for medical diagnosis applications. SPECT is a widely used imaging modality in medicine which uses radio-pharmaceuticals labelled with gamma emitting radioisotopes such as 99mTc and 123I. The method is used to study physiological functions in many areas of medicine, such as oncology (cancer imaging) and neurology (brain function). Existing SPECT systems have a limiting position resolution of about 10 mm for body imaging and 7 mm for the head. The proposed system will offer an image resolution of 2-3 mm with a sensitivity a factor of ~100 larger than existing systems. The system will be designed to operate with a Magnetic Resonance Imaging (MRI) system and will therefore enable SPECT/MRI multimodality imaging. This is hugely important as it allows simultaneous anatomical and functional imaging studies to be performed.

The consortium brings together academic partners from the Nuclear Physics Group in the Department of Physics at University of Liverpool and the Nuclear Physics & Technology Groups at STFC Daresbury Laboratory. This brings together groups with internationally leading reputations and many years experience with semiconductor radiation detectors, electronics and software design. Key clinical input and trials are provided through Clinicians at the Clatterbridge Centre for Oncology , the University of Liverpool Magnetic Resonance Imaging Analysis Research Centre [MARIARC] and the Interventional Radiology and Medical Imaging Group at the Royal Liverpool University NHS Trust.

Professor S Chattopadhyay, University of Liverpool, ‘Compact radio-frequency linear accelerator technology with dynamic RF power controls for applications in cargo and global security’, funds awarded £644,250. Start date 1 July 2009 until 30 June 2011.

The large volume of cargo transported around the world on a daily basis presents a significant security challenge for society today. The range of territories, methods and organizations involved in the movement of cargo necessitate smart, compact, rapid and cost effective detection systems in bulk for diverse and distributed use. There has been limited but successful experience in the past with imaging by X-rays derived from radiation from a metal target irradiated by electron beams of few million-volts of energy. Such systems are in use at airports and in sensitive zones of combat and conflict around the globe.

We plan to further develop this technology to produce a series of compact X-Ray sources required for integration in a new series of cargo and vehicle inspection systems. These will be able to scan rapidly for sub-mm resolution and have the ability to discriminate between different material composition (solid, liquid, gas, flammable, explosive, nuclear, etc.) in bulk volumes of a cubic meter scale. The system will be required to switch rapidly between different X-ray spectra by varying the energy in rapid cycle. The Cockcroft Institute has been involved in the development of compact ‘X-band linear accelerator’ technology for high energy particle colliders. This technology uses high frequency RF accelerating cavities to produce compact high gradient accelerating structures. Further development of this X-band technology will provide compact, flexible and cost-effective X-ray sources which can be used in diverse mobile security scanning applications. RapiScan Inc., well-known for its scanning systems around the world and e2V Inc., one of the oldest premier microwave industries in UK, will be collaborators with the Cockcroft Institute on this project.

Dr RJ Nichol, UCL, ‘CREAM TEA – Phase 1’, funds awarded £125,000. Start date 1 July 2009 until 30 June 2011.

CREAM TEA (the Cosmic Ray Extensive Area Mapping for Terrorism Evasion Application) combines a method pioneered in the 1950’s with modern particle physics detector technology to search large volumes for unusual dense foreign objects.

Using information provided by cosmic ray particles, which are either absorbed or scattered in the target volume, and tomographic techniques it is possible to create three dimensional density images in an analogous manner to x-ray imaging.

In the last 50 years cosmic rays have been used to image objects ranging from Australian mines to Japanese volcanoes, and most famously to search for hidden chambers in the pyramids of Egypt.

Cosmic ray muons could provide one approach to the problem of how to monitor a large crowded area such as a train station. By instrumenting train stations with cosmic ray detectors it may be possible to continuously scan for deposited items, particularly (although not limited to) those of high density such as fissile materials or nail bombs.

Phase-I of the CREAM TEA project is a 12 month feasibility study, which will use computer simulations to determine the amount of time and required detector resolution to successfully image large volumes for potential terrorist devices. The results of these simulations will be validated using a laboratory test stand detector. If the feasibility studies prove successful, the next phase of the CREAM TEA project will result in the design and construction of a full-size prototype detector.

Dr A Nomerotski, University of Oxford, ‘PImMS: Fast CMOS sensors for imaging mass spectrometry’, funds awarded £736,173. Start date 1 July 2009 until 30 June 2012.

Mass spectrometry is a powerful analytical technique widely used to identify unknown compounds and to elucidate the structure of molecules. The PImMS (Pixel Imaging Mass Spectrometry) project is developing a fast imaging sensor for use in a next-generation time-of-flight mass spectrometer (TOF-MS) with unique imaging capabilities. Recent progress in semiconductor technologies presents the opportunity to produce a novel detector that will allow us to marry the ion-imaging technique with mass spectrometry. For each mass, the new instrument will image with high precision the complete velocity or spatial distribution of the ions at their point of formation. This will take mass spectrometry from its current role as a one-dimensional ‘weighing’ technique into a multi-dimensional world, in which spatial, velocity, and even coincidence information is provided as a function of mass. The novel pixel detector used in the instrument will be based on the deep submicron CMOS process INMAPS, originally developed by STFC-RAL for use at the International Linear Collider.

Potential applications are wide-ranging. In spatial mapping mode key applications will be in ‘single shot’ molecular imaging of surfaces, and in high-throughput sampling; the extra spatial dimension will allow conventional mass spectra of large numbers of samples to be acquired in parallel, potentially enabling faster and more efficient use of mass spectrometry. In velocity mapping mode the technique will find important applications in molecular fragmentation studies, providing important structural information in addition to the fragment masses which could be important in understanding complex organic molecules.