How to produce a compact X-ray and gamma-ray radiation source

Step One
Take a light pulse from a table-top, high-power, femtosecond laser system (high-spec but commerically available all the same).

           Femtosecond laser beam

Step Two
Focus the laser pulse into a capillary channel containing plasma (a fully ionised gas) that's some centimetres long and less than a millimetre wide.

Miniature electron accelerator

You've now obtained a high energy bunch of electrons. High energy means high energy - the electrons are travelling at virtually the speed of light. They are produced by a very compact device: the laser-plasma wakefield accelerator. Conventional accelerators use microwave cavities which require vastly larger infrastructure to achieve the same electron energy.

Step Three
To produce short wavelength radiation pulses (e.g. ultraviolet light, X-rays or gamma-rays) the electrons are forced to wiggle very rapidly. This is can done using an array of magnets called an undulator or, to make it even more compact, using the electromagnetic fields of the plasma itself. This wiggling motion produces synchrotron radiation or betatron radiation - tunable from the visible to gamma-rays.

Undulator magnets                           

Three steps to producing short pulses of radiation which could be powerful tools for scientists, the medical world and engineers. Their availability could revolutionise the way science is done - because they are very compact and relatively inexpensive.

The ALPHA-X compact radiation light source

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