Just like a bear after its winter sleep, CERN’s big machines are gradually awakening after the extended year-end technical stop (EYETS). The first beams for 2017 are expected to circulate in the Large Hadron Collider (LHC) in early May, but before that the accelerator complex and all the experiments that it serves have to be put back into operation, one after the other.

In the first week of April, the Linear Accelerator 2 (Linac 2), the starting point of the protons used in CERN's experiments, successfully accelerated its first proton beam and prepared it to be sent to the Proton Synchrotron Booster (PSB).

On 10 April, the PSB was also restarted. As the second element in the chain, the PSB increases the energy of the beam received from Linac 2 and sends it to either the Proton Synchrotron (PS) or to the Isotope Mass Separator On-Line facility (ISOLDE).

The next step is to put the Proton Synchrotron (PS) back in operation from today (13 April). This is the oldest accelerator still in service and is currently the third component in the accelerator chain. It pushes the beams to even higher energies and sends them to the Super Proton Synchrotron (SPS), the last element in the accelerator chain before the LHC. It also feeds the East Area where the Cosmics Leaving Outdoor Droplets (CLOUD) experiment is situated, the Antiproton Decelerator, and the Neutron Time-of-Flight Facility (n_TOF).