Brightness and Emittance
The research that can be carried out in the Beamlines is closely linked to the quality of light produced by the Source. The quality of a Synchrotron Light Source is characterized by its brightness, defined as the number of photons emitted by the source in a determined spectral range of energy, per unit time, per unit size and angular divergence of the source. The higher the brightness, the better the quality of the light source.
Some scientific applications and experimental methods can only be carried out in light sources with high brightness and coherence. Thus, there is a constant search for building synchrotrons increasingly bright, from which Sirius stands out for being designed to have the highest brightness in the world among the sources with its energy range.
One of the most effective ways to increase the brightness of light sources is the reduction of a quantity called emittance. The emittance of a synchrotron light source is a measure of the size and angular divergence of the electron beam. The better collimated is the electrons beam, that is, the lower the emittance, the higher the brightness of the source.
In turn, emittance, which is a constant feature of the machine and depends only on the configuration of the magnetic lattice of the Storage Ring, which is one of the main parameters of a Synchrotron Light Source.