The Booster is a Synchrotron accelerating the electrons coming from the Linac to the final energy of 2.4 GeV. It has a circumference of 270 m and consists of a variety of itemssuch as an RF station, vacuum components, diagnostic tools and a total of 237 magnets. During acceleration the magnetic fields are constantly adapted to the corresponding energy of the electrons. After extracting the electrons from the booster the magnetic fields are then restored to their initial values. This process is periodically repeated 3 times per second. It takes then several minutes to fill the storage ring with the desired quantity of electrons (several trillions!).
At the final energy the speed of the electrons is so close to the speed of light, that in a race to the moon the light would be only 8 m ahead of the electron!
After extraction from the booster the electrons are guided in a 20 m long beam transport system towards the injection point of the storage ring.
The SLS booster is located in the same tunnel as the storage ring. It was especially designed to produce a high-quality electron beam for the so-called top-up injection. In this mode the booster injects periodically electrons into the storage ring, keeping the intensity of the circulating electron beam constant.
