Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First demonstration of new laser-driven accelerator technology

30.09.2004


A team of UK scientists has used, for the first time, an extremely short-pulse laser to accelerate high-energy electrons over an incredibly short distance. Current accelerators can be hundreds of metres long, this is just a millimetre long.

Earlier laser-driven accelerators were inefficient, accelerating the electrons to a wide range of energies. But scientists who wish to use these electron beams to research materials science – such as the structure of viruses and moon rock – need the electrons to have the same energy. The team of scientists, led by Imperial College London and including scientists from the CCLRC Rutherford Appleton Laboratory, the University of Strathclyde and University of California, Los Angeles, has shown for the first time that a laser-driven accelerator can produce a beam of electrons with a narrow range of energies. The results of this experiment will be published in Nature on 30 September 2004.

The experiment was performed at the CCLRC Rutherford Appleton Laboratory near Oxford using the Astra laser. This major breakthrough represents a step towards a new technology which promises to be much cheaper and more compact than the conventional approach and in the future could allow individual universities to afford these accelerators instead of relying on large national laboratories.



Currently there are a few large-scale accelerators around the world, such as CERN - the European laboratory for high energy physics research in Geneva, which is about 10 km across. As scientists try and probe the universe at smaller and smaller scales they need higher energy beams – the current accelerator technology means that the only way to achieve this is to make even bigger accelerators. "Scientists all accept that before long we’ll need a completely new approach to producing the beams of particles required for next generation light sources and high energy physics research. In this experiment we’ve proved that compact, high power lasers can offer a viable new technology,” says Stuart Mangles, one of the researchers from Imperial College London.

Professor Karl Krushelnick from Imperial College London led the team of researchers and explains that though this result is scientifically very significant, it is only the start of further research. "The next step is to increase the energy of the electrons from these laser-driven accelerators – either by increasing the length of the accelerator or by increasing the laser power. We’re still some way off producing a beam of electrons that could be useful for X-ray radiation sources and high energy physics but we’re all really excited by this major step forwards”.

The initial concept of laser Wakefield accelerators was first discussed 25 years ago. It has only been in the last 10 years that the technology has enabled the theory to be realized. Laser Wakefield accelerators were first proposed in 1979 by Toshi Tajima and John Dawson in a famous paper in Physical Review Letters. When an intense laser pulse is focused into a region of gas (helium in these experiments) it ionizes the gas, turning it into a plasma, and can set up a wave travelling behind the pulse at very nearly the speed of light. “This plasma-wave generates a very large electric field that is more than 100 times greater than the electric field of conventional accelerators, and this accelerates the electrons much like surfers are carried along on a wave at a beach,” explains Chris Murphy, another member of the research team based at the Rutherford Appleton Laboratory.

Previous experiments have relied on these plasma waves breaking (just like when a wave breaks on a beach) to produce large numbers of energetic electrons but this wavebreaking process has always produced an unwanted large energy spread. By carefully controlling the laser and plasma parameters the Imperial College team has shown that it is possible to use wavebreaking to produce beams of electrons with a narrow energy spread. That’s why electrons are accelerated to 70MeV in this experiment over a length of just 0.6mm, compared with many metres in a conventional accelerator.

The research was supported through the Research Councils’ Basic Technology Research Programme, which is managed by EPSRC (Engineering and Physical Sciences Research Council) on behalf of all the research councils.

Jacky Hutchinson | alfa
Further information:
http://www.cclrc.ac.uk

More articles from Physics and Astronomy:

nachricht Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University

nachricht Nano-watch has steady hands
22.11.2017 | University of Vienna

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>