An experiment to recreate a natural phenomenon associated with the polar lights could also shed light on an experimental energy source: fusion power.
Plasma physicist Dr Kevin Ronald led a research team to successfully recreate auroral kilometric radiation (AKR) in the lab, reducing a vast environment into an experiment that measures just 10 centimetres across.
AKR is a powerful radio wave produced 3,000 kilometres above the Earth's surface when electrons orbit in the Earth's magnetic field, converting electron energy into wave energy.
Dr Ronald said: "The most curious point for physicists when AKR was discovered was the efficiency of conversion process. It is exceptionally efficient for a natural phenomenon and implies a collective, coherent process."
A research team set out to determine whether the conversion efficiency could be explained by the rotating motion of the electron beam in the Earth's magnetic field.
Working with Professor Bob Bingham (University of Strathclyde and the Rutherford Appleton Laboratory) and Professor Alan Cairns (University of St Andrews), Dr Ronald and his colleagues have built an experiment that replicated major features of the auroral environment.
Measurements to date show comparable conversion efficiency to the natural phenomenon and these results also compare well with the team's numerical and theoretical calculations.
Although the project began out of pure scientific curiosity, the apparatus used for experiments may also prove useful for applied research into energy production by nuclear fusion.
Dr Ronald said: "Fusion energy techniques under research at the moment face fundamental problems in plasma physics. Many of these problems are associated with the presence of high energy particles travelling through an ionised gas (plasma)."
"The auroral kilometric radiation experiment apparatus is being developed to demonstrate the same type of physics but in a more accessible environment with lower temperatures and lower energy densities. We want to do controlled experiments to look at how the directed energy in the 'beam' particles is converted to random thermal energy in the bulk plasma."
The research is relevant to both the European HiPER High Power Laser Energy Research project and the ITER (International Thermonuclear Experimental Reactor) magnetic tokamak project to demonstrate fusion energy.
Dr Ronald says the research demonstrates the scalability of plasma physics.
"By understanding a certain set of fundamental physical laws you can describe apparently diverse things that actually turn out to be quite similar - it's the same science that covers it all."
Who's involved?
- University of Strathclyde: Dr Kevin Ronald, Dr David Speirs, Miss Sandra McConville, Ms Karen Gillespie, Dr Adrian Cross, Professor Alan Phelps, Dr Colin Whyte, Dr Craig Robertson, Dr Wenlong He, Mr Martin King, Mr Ross Bryson.
- Rutherford Appleton Laboratory: Professor Bob Bingham (part-time University of Strathclyde), Dr Barry Kellett and Dr Raoul Trines.
- University of St Andrews: Professor Alan Cairns, Dr Irena Vorgul
Members of the project team are connected to the UK centres for fusion research at the Rutherford Appleton and Culham laboratories.
Who funds the research?
The research is funded by the Engineering and Physical Sciences Research Council and the Science and Technologies Facilities Council's Centre for fundamental physics.
Where does the research happen?
Visit the Facilities & Resources webpage to learn about Strathclyde's specialist plasma physics laboratory.