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The accelerators awaken

The accelerator chain and the experiments that it serves are gradually awakening after the extended year-end technical stop (EYETS)


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 ISOLDE facility has gathered unique expertise in research with radioactive beams. Over 700 isotopes of more than 70 elements have been used in a wide range of research domains, from cutting edge nuclear structure studies, through nuclear astrophysics, to solid state and life sciences. 

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). 

The purpose of n_TOF is to study neutron-nucleus interactions, which play a key role in neutron-related processes, important in a wide range of context, from astrophysics, to hadrontherapy (the treatment of tumors with beams of hadrons), and the development of retreatment of nuclear waste.