Synchrotron light source
A synchrotron light source is a source of electromagnetic radiation (EM) usually produced by a storage ring,[1] for scientific and technical purposes. First observed in synchrotrons, synchrotron light is now produced by storage rings and other specialized particle accelerators, typically accelerating electrons. Once the high-energy electron beam has been generated, it is directed into auxiliary components such as bending magnets and insertion devices (undulators or wigglers) in storage rings and free electron lasers. These supply the strong magnetic fields perpendicular to the beam that are needed to stimulate the high energy electrons to emit photons.
This article is about the laboratory production and applications of synchrotron radiation. For details of physics of emission and properties, see synchrotron radiation.
The major applications of synchrotron light are in condensed matter physics, materials science, biology and medicine. A large fraction of experiments using synchrotron light involve probing the structure of matter from the sub-nanometer level of electronic structure to the micrometer and millimeter levels important in medical imaging. An example of a practical industrial application is the manufacturing of microstructures by the LIGA process.
Synchrotron is one of the most expensive kinds of light source known, but it is practically the only viable luminous source of wide-band radiation in far infrared wavelength range for some applications, such as far-infrared absorption spectrometry.
Especially when artificially produced, synchrotron radiation is notable for its:
Compact synchrotron light sources[edit]
Because of the usefulness of tuneable collimated coherent X-ray radiation, efforts have been made to make smaller more economical sources of the light produced by synchrotrons. The aim is to make such sources available within a research laboratory for cost and convenience reasons; at present, researchers have to travel to a facility to perform experiments. One method of making a compact light source is to use the energy shift from Compton scattering near-visible laser photons from electrons stored at relatively low energies of tens of megaelectronvolts (see for example the Compact Light Source (CLS)[21]). However, a relatively low cross-section of collision can be obtained in this manner, and the repetition rate of the lasers is limited to a few hertz rather than the megahertz repetition rates naturally arising in normal storage ring emission. Another method is to use plasma acceleration to reduce the distance required to accelerate electrons from rest to the energies required for UV or X-ray emission within magnetic devices.