Synchrotron light is an electro magnetic radiation generated by charged particles travelling at speeds close to the speed of light that move along curved trajectories, due to the effect of magnetic fields, in accelerating machines called synchrotrons. This radiation, which for all intents and purposes is a light with wavelengths ranging from infrared to X-rays, has some characteristics that make it unique: it is billions of times brighter than the one generated by conventional sources and allows a broad range of applications, both in research and industry.
Over the last decades, the use of synchrotrons by the scientific community has opened new perspectives for the study of the matter. Currently, there are more than 60 synchrotrons worldwide, with continuously increasing requests for their use. In view of the extensive use of such machines, in recent years great progress has been made in the implementation of even stronger sources of electromagnetic radiations complementing synchrotrons: these are called “Free Electron Lasers” (FEL) and are based on linear accelerators (Linac) for electrons and on chains of magnetic devices called “undulators” in which electromagnetic radiation is extracted from the electron beam by means of principles similar to those of synchrotrons.
The photon flux emitted by a FEL is many orders of magnitude greater than the one produced by current synchrotrons, and nowadays the FEL is the most powerful instrument for basic research on matter. Unfortunately, considering increasingly growing requests in terms of “beamtime”, FEL sources are not very diffused, not least because of their high investment costs. The “CompactLight (XLS)” project, funded by the Horizon 2020 European programme and co-ordinated by the Elettra Sincrotrone Trieste laboratory, is aimed at implementing extremely compact FEL sources characterised by cutting-edge performance and low cost, so as to allow their diffusion even in those contexts where only limited research budgets are available.
This co-operation, launched by a team of 22 International Laboratories and two Industries, brings together world experts in the fields of accelerators and magnetic structures for photon production. “The objective is to use the most innovative technologies for the implementation of the main components of a FEL: high brightness photo-injectors of the last generation, compact and very high-gradient X-band accelerating structures to increase the global efficiency of the machine as well as state-of-the-art undulators, to be able to produce high-energy photons at lower electron beam energies in comparison with current machines.” CompactLight will also contribute to give a large boost to several high-technology sectors, from microwaves to mechanical precision engineering.