1 March 2021
Giorgio Margaritondo (Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
FEL basics, generation and applications
A basic knowledge of FELs, in turn supported by an equally basic knowledge of synchrotron radiation, is very useful in fully exploting the wonderful properties of these sources. Unfortunately, the standard presentations tend to be very complicated and primarily oriented towards accelerator experts. However, the corresponding physics is quite simple and does not require an advanced knowledge of theoretical physics, but only the most elementary notions of special relativity. Indeed, most if not all the synchrotron and FEL properties can be presented in a simple form and without complicated mathematics: this is our objective. We shall start with an elementary introduction of synchrotron radiation, including properties like the emitted wavelengths, flux, angular collimation, brightness and coherence. Then, we shall introuduce the FEL mechanism, explaining fundamental properties like bunching, coordinated emission and the time structure. This will be the gateway to some of the FEL applications, such as femtosecond experiments and new techniques based on fundamental quantum properties. In summary, with this lecture the audience will become familiar with relevant properties and understand what is the simple physics behind them.