Synchrotron radiation (SR) is generated when highly relativistic charged particles (typically electrons or positrons) are forced to follow a curved trajectory in strong magnetic fields. as a result of the radial acceleration of these high-velocity charged particles, orbiting at speeds (v) of nearly the speed of light (c), electromagnetic radiation is generated which covers a wide wavelength (energy) range and has unique properties for spec-troscopic studies. Synchrotron radiation is emitted tangentially to the electron path, in the form of a narrow cone of intense electromagnetic beam (Fig. 1).

This type of radiation is generated in so-called electron (or positron) storage rings, which consist of an evacuated, quasi-circular vacuum chamber coupled with a lattice of magnets, in which electrons/positrons can circulate freely in a closed orbit (Fig. 2). The path of the charged particles within the storage ring is determined by the magnetic lattice within the ring, which both focuses and bends the beam of charged particles, keeping it in a closed trajectory.

The so-called first generation synchrotron storage rings were built for particle physics experiments, high-energy particle accelerators, in which the synchrotron radiation generated was considered to be an unwanted by-product, resulting in an energy-loss for the accelerated particles. In the 1960s, scientists began to use synchrotron radiation from several of these first generation accelerators in a ‘parasitic mode’, realizing that the synchrotron radiation emitted has very advantageous properties for many types of spec-troscopic applications.