Researchers create extremely hot and dense plasma

Plasmas such as this one differ markedly from well-characterised dilute ‘gaseous’ plasmas and could simulate conditions within stars with a view to emulating fusion power.

The team carried out the experiments at the Linac Coherent Light Source (LCLS) within the US Department of Energy (DOE), which creates X-rays.

‘There is unfortunately no comparable facility in the UK,’ said project collaborator Dr Sam Vinko of Oxford University.

‘Although Diamond [Light Source, at Harwell] is a high spectral-brightness X-ray source compared to other synchrotrons, that is, other third-generation light sources, the spectral brightness of LCLS is more than a billion times greater. This puts it into a whole new league in terms of the science one can do.’

Scientists have long been able to create plasma from gases and study them with conventional lasers, but until now no tools have been available for doing the same at solid densities.

‘Conventional lasers cannot penetrate such systems but are reflected off their surface, so we cannot see inside them. Also, once heated they tend to blow up very quickly, making them extremely short-lived and necessitating ultra-fast diagnostics,’ said Vinko.