The project was originally conceived as a test bed for the 4th Generation Light Source (4GLS), and consists of: The ALICE accelerator is an Energy Recovery Linac (ERL) that incorporates all the features of the 4th generation light source albeit at smaller scale.
The ability to produce ultra-short electron bunches well below 1ps and an availability of several light sources of different "colour" open up numerous possibilities for conducting investigations of fast processes on a femtosecond scale in molecular and solid state physics to name but a few.
A DC photoelectron gun generates short low emittance electron bunches with the length of several picosecond (ps) and accelerates them to a modest 350keV.
After compression, the beam, consisting now of sub-picosecond bunches, enters the magnetic undulator that constitutes a major part of the mid-IR Free Electron Laser (FEL).
This condition requires an accurate adjustment of the electron beam path length that is accomplished by moving the ARC1 as a whole.