First Beam in the Energy Recovery Linac Prototype at Daresbury

http://www.4gls.ac.uk/news.htm

An idea, which has huge potential for the next generation of particle accelerators and storage rings,is now being pursued at a number of accelerator laboratories worldwide. It concerns the possibility of a ring in which electrons are stored at a specified energy for only one, or may be a few "round-trips", at design energy. During storage, the electrons are manipulated in a number of ways to produce radiated energy - photons - with characteristics in terms of wavelength, intensity, and time structure which have been hitherto impossible.

While stored, the properties of the stored electron beam are severely disturbed by their manipulation to produce the photon radiation. Thus, for a new "round-trip", the energy is recovered and transferred to a new beam of electrons for a new cycle of emission of radiation. Thus, by means of "energy recovery", an "energy storage and delivery ring" is made possible.

Scientists and engineers at the Daresbury Science and Innovation Centre (DSIC) have just succeeded in getting first beam from an electron source, a laser-driven gun, into the injection system for their prototype, energy recovery, linac, the ERLP. This is the first step in the commissioning of the ERLP, which is aimed at establishing proof-of-principle of the energy recovery idea. In the next few months, beam will be injected into the ERLP ring, and first evaluation of the performance of energy recovery will follow.

Once the technology of energy-recovery is established, it will then be possible to demonstrate for the first time the principle underlying the "4th generation" of "light sources", that is of accelerator systems which will deliver photon radiation in revolutionary new ways. Daresbury scientists and engineers have a proposal for a 4th generation machine, called 4GLS, which is well advanced in design. When built, 4GLS will be a unique "light source", comprising synchrotron radiation and a free electron laser (FEL), which will make possible a whole new swathe of "cutting edge" science, medicine and engineering for decades to come. Other 4th generation machines are planned worldwide, some are FEL sources and some plan an "Energy Recovery" principle now being pioneered at Daresbury and in the USA.

The commissioning of the ERLP is in the hands of the ASTeC group and members of the 4GLS team. ASTeC have recently moved to the Cockcroft Institute at the DSIC, joining colleagues from the universities of Lancaster, Manchester and Liverpool. The commissioning work is being pursued by a team which includes accelerator physicists and engineers from the Institute. Many of the new techniques, which have to be developed and mastered at the ERLP, are generic to the next generation of accelerators worldwide. Thus, as well as being the next vital step in the realisation of 4GLS and other 4th generation light sources, the ERLP also contributes to the development of the new technologies which underpin new accelerators worldwide. These accelerators are aimed at a wide range of science, including the fundamental physics of the Universe, chemistry and the development of new materials, biomolecular science and progress in medicine treatment and diagnosis, and industrial applications such as lithography in nano-engineering. Cockcroft Institute staff, many of whom work on accelerator projects in Europe, Japan and the USA, facilitate the important synergy and interaction between the important work on the ERLP and on these other cutting edge machines