There is so much happening across Glasgow and the West of Scotland and our news portal will allow us to share it with you.

Atomic ‘Trojan horse’ for a new generation of X-ray lasers

Illustration, based on simulations, of the Trojan horse technique for the production of high-energy electron beams. Image by Thomas Heinemann/University of Strathclyde

An intense electron beam that could be used in the X-ray lasers of the future has been produced in research led at the University of Strathclyde.

The beam was created by the plasma photocathode method, in which electrons were released from neutral atoms inside plasma.

This has produced a potentially much brighter, plasma-based electron source which could be used in more compact, more powerful particle accelerators.

The research has been carried out as part of the ‘E-210: Trojan Horse’ experiment at the Facility for Advanced Accelerator Experimental Tests (FACET) at the Stanford Linear Accelerator Center in California, and is now published in Nature Physics.

Professor Bernhard Hidding, of Strathclyde’s Department of Physics, principal investigator in the study, said: “Our experiment demonstrates the feasibility of one of the most promising methods for next-generation electron sources and could push the boundaries of today’s technology by orders of magnitude.”

According to calculations by Professor Hidding and his research colleagues, the Trojan Horse technique could make electron beams 100 to 10,000 times brighter than today’s most powerful beams.

Brighter electron beams would also make future X-ray lasers brighter and further enhance their scientific capabilities.

In current state-of-the-art accelerators, electrons are generated by shining laser light onto a metallic photocathode, which displaces electrons from the metal.

These electrons are then accelerated inside metal cavities, where they draw more and more energy from a radiofrequency field, resulting in a high-energy electron beam.

In X-ray lasers, this electron beam drives the production of extremely bright X-ray light. 

However, metal cavities can support only a limited energy gain over a given distance, or acceleration gradient, before breaking down, and therefore accelerators for high-energy beams become very large and expensive.

In recent years, scientists have looked into ways to make accelerators more compact.

They demonstrated, for example, that they can replace metal cavities with plasma that allows much higher acceleration gradients, potentially shrinking the length of future accelerators by 100 to 1,000 times.

This is a central thrust of the Scottish Centre for the Application of Plasma-based Accelerators (SCAPA) at the University of Strathclyde.

The new paper expands the plasma concept to the electron source of an accelerator.

First, the research team sent laser light into a mixture of hydrogen and helium gas. The light had just enough energy to strip electrons off hydrogen, turning neutral hydrogen into plasma.

It was not, however, energetic enough to do the same with helium, which has electrons that are more tightly bound than those of hydrogen, and so it stayed neutral inside the plasma.

The scientists then shot an electron bunch through the plasma, where it produced a plasma wake, much like a motorboat creates a wake when it glides through the water. Trailing electrons can ‘surf’ the plasma wake and gain tremendous amounts of energy.

A second laser pulse was then flashed into the plasma, this time intense enough to liberate electrons from helium. If the timing is right, the ultracold helium electrons from this plasma photocathode are then rapidly captured by the plasma wave and produce a new, much brighter beam of electrons. 

The researchers have also developed several auxiliary techniques, which allow them now improving the quality and stability of their output beams, and to harness the technique for applications.

A central experimental pathway for this will be the 'E-310: Trojan Horse-II' flagship collaboration at SLAC’s follow-up facility FACET-II, complemented by R&D in the UK at SCAPA and Daresbury Lab’s CLARA, and in Europe in context of the H2020 effort EuPRAXIA.



University of Strathclyde

No Comments...

Add a comment

01 05 02 04 Audio Captcha
Add Comment


What’s happening

This is a living, breathing website with regular updates on news, blogs and events. It’s the place to come back to again and again if you want to know what’s happening in the science and technology world in Glasgow and the West of Scotland.

Subscribe to keep up to date on our latest news, blog posts and events.



Scientists discover novel viruses carried by the Scottish midge

Scotland’s biting midge population carries previously-unknown viruses, according to new research. ...


Glasgow makes top six cities in European Capital of Innovation competition

Glasgow has been named as one of six finalists in the European Capital of Innovation competition, a ...


Glasgow student helping to empower Africa’s young scientists

A University of Glasgow student is using maths and computing skills to train young scientists in Afr...




Grounds to create global change

To mark International Zero Waste Week Scott Kennedy, co-founder of Revive Eco and member of Industri...


Learning to fuel the growth of a more sustainable world

Rachel Clark from the Industrial Biotechnology Innovation Centre (IBioIC) encourages students into s...


Glasgow City Region – a new European City Region of Innovation

Glasgow City Region is emerging as a new European City Region of Innovation. Kevin Rush, Director of...




Explorathon: Glasgow Skeptics -- Precision Medicine

Glasgow Skeptics present an exciting talk to discuss the medicinal developments in the field of rheu...


Apollo 11

Documentary marking the 50th anniversary of the first moon landing with never-before-seen footage an...


International Space Station Flight Control

When astronauts call Earth, Andrea Boyd answers. Stationed at the European Astronaut Centre in Colog...


previous post next post