The European Organization for Nuclear Research (CERN) celebrated the completion of its Linac 4 during a ceremony on May 9. The new accelerator is expected to allow the facility’s Large Hadron Collider (LHC) to reach higher luminosity by 2021. The machine is almost 90 meters long, sits 12 meters below the ground and took nearly 10 years to build. Engineers will now begin an extensive test period and hope to connect the instrument to CERN’s accelerator complex over the facility’s long technical shutdown in 2019-20.
“We are delighted to celebrate this remarkable accomplishment,” says Fabiola Gianotti, CERN’s director general. “Linac 4 is a modern injector and the first key element of our ambitious upgrade program, leading up to the High-Luminosity LHC. This high-luminosity phase will considerably increase the potential of the LHC experiments for discovering new physics and measuring the properties of the Higgs particle in more detail.”
Once integrated, Linac 4 will replace Linac 2 to become the first step in CERN’s accelerator chain, producing particles and providing the initial acceleration to deliver proton beams to a wide range of experiments. The accelerator will also shape the density and intensity of the particle beams.
CERN says that Linac 4 will bring the beam up to 160 MeV energy, more than three times the energy of its predecessor. The increase in energy, together with the use of hydrogen ions, is expected to double the beam intensity to be delivered to the LHC, thus contributing to an increase in the luminosity of the LHC.
Luminosity is a parameter indicating the number of particles colliding within a defined amount of time. CERN plans to increase the peak luminosity of the LHC by a factor of five by 2025, making it possible for its experiments to accumulate about 10 times more data over the period from 2025 to 2035.