My research interests are in theoretical plasma physics, particularly in the hot plasmas relevant to nuclear fusion research, the interaction of high power lasers with matter and some problems in space and astrophysics. The common thread amonst these problems is that they involve the propagation and absorption of waves and acceleration of particles by waves. Recently I have been working in collaboration with UKAEA Fusion on heating and current drive in magnetically confined plasmas, and on two separate projects involving collaborations amongst a variety of institutions. Two successive linked grants from EPSRC to St Andrews and Strathclyde have supported a joint programme of research on theory and experiment related to the emission of radio waves from the Earth's auroral regions and other planets and stars.  A mechanism which we have investigated theoretically has been verified by the Strathclyde experiment to behave as predicted. Another project with which I have been involved is a large collaboration, led by Strathclyde and involving a number of UK institutions.  This £4.4 project, known as Alpha-X is aimed at using electrons accelerated by a laser to drive a free electron laser and produce intense coherent X-ray emission. Proof of principle of this idea is likely to be obtained soon. I am co-investigator on two EPSRC grants which have been awarded to support further investigation of some aspects of this work.

For further information, see the Plasma Physics Research Group site.

My research interests are in theoretical plasma physics, essentially in areas which involve wave propagation and absorption and particle acceleration by waves.  In recent years the major projects in which I have taken part are the following.

1. Current drive in spherical tokamaks using Bernstein modes.  The latter are waves which propagate in a hot plasma around harmonics of the electron (or ion) cyclotron frequency. The normal electron cyclotron mode cannot reach the centre of the plasma in spherical tokamaks, because of their relatively low magnetic field, hence the interest in Bernstein modes.  UKAEA Fusion have supported a postgraduate student (Duncan McGregor) to carry out work on this problem.  He has successfully produced computer codes which deal with the fully relativistic electromagnetic dispersion relation of these waves then gone on to implement an approximate method for estimating their efficiency for current drive. This extends a method proposed by some other authors for the usual electromagnetic mode, and takes into account the toroidal geometry of the machine. Tests of this method against numerical Fokker-Planck codes has shown that it can give a good estimate of the current drive efficiency in a fraction of the time needed to run a Fokker-Planck code.  Duncan's codes have been implemented at Culham.

2. Theory of auroral kilometric radiation (AKR) and related processes.  A few years ago I analysed, in collaboration with Robert Bingham of the Rutherford Appleton Laboratory, an instability which seems relevant to AKR and related radio emission processes from other planets and some stars. We then began a collaboration with Alan Phelps and his group in Strathclyde, who are expert on devices for producing radiation from, devices using electon beams.  With the support of two successive linked EPSRC grants to St Andrews and Strathclyde we have continued the theoretical analysis and also constucted an experiment to reproduce, on a laboratory scale, the mechanism we believe responsible for AKR.  The experiment has now produced radiation whose spectral properties and efficiency of conversion of energy from the electron beam are in close agreement with the observed properties of AKR. This subject will be an important part of my activities for the next few years.

3. The Alpha-X project. This is a project, coordinated by Dino Jaroszynski at Strathclyde and involving groups from Imperial College, Oxford, Dundee,  Rutherford Appleton Laboratory, Daresbury Laboratory and St Andrews. The objective, supported by a Basic Technology grant from the UK Research Councils (of around £4.4M), has been to produce a high energy electron beam using laser acceleration techniques, then to use this beam to drive a free electron laser producing coherent emission in the X-ray frequency range.  This project is nearing an end, has produced important results and is close producing a proof of principle of this method.  I am already co-investigator on a project arising from this, on short laser pulse amplification by Raman scattering, which has been awrded funding by EPSRC through Strathclyde. A further large EPSRC grant for continuation of the project was approved in November 2006.

For further information, see the Plasma Physics Research Group site.

General expertise in the use of mathematics to model physical systems.

I expect to continue work in the areas outlined above and also to look out for other problems to which my expertise is relevant.

My work is relevant to research on contrlloed nuclear fusion.  The work on AKR may be relevant to laboratory devices for radiation generation.  The Alpha-X project is aimed at eventually producing a compact source of high intensity coherent X-rays which could have medical and industrial applications.