The surface above the PS Booster at CERN. The ring-shaped accelerator is visible as a circular building that rises from the ground.
The Proton Synchrotron Booster (PSB), a synchrotron, is the first and smallest circular proton accelerator in the accelerator chain at the CERN Large Hadron Collider injection complex. The accelerator was built in 1972, and contains four superimposed rings with a radius of 25 meters. It takes protons with an energy of 50 MeV from the linear accelerator Linac2 and accelerates them up to 1.4 GeV, ready to be injected into the Proton Synchrotron.