The CERN Accelerator Complex

Dr. Masoomeh Yarmohammadi Satri

School of Particles and Accelerator, IPM

Tuesday, 19 Ordibehesht 3:00-4:00 pm

Ibn Al-Haytham Hall, Physics Department

Host: Dr. Ghasemkhani

The Large Hadron Collider (LHC) project was approved by CERN council on 1994 and commissioned in 2008, after fifteen years of construction, aimed to provide two directions proton beams of 7TeV to collide at four experiments: ALICE, ATLAS, CMS and LHCb. The CERN accelerator complex contains: Linac2/Linac3, Proton Synchrotron Booster (PSB)/Low Energy Ion Ring (LEIR), Proton Synchrotron (PS), Super Proton Synchrotron (SPS) and LHC. The linear accelerator, linac, is the first stage of any hadron accelerator complex. The generated transverse and longitudinal beam emittances with linac defines the beam quality for the next stages of acceleration and the reliability of the linac injector has to be high since a fault of the linac shuts down all other machines. A 50MeV proton linac, Linac2, was commissioned in 1978, and is the workhorse of the accelerator complex. Linac4 is a 160MeV H-linear accelerator will replace Linac2 to increase the beam brightness as the preliminary step of the CERN Large Hadron Collider injectors upgrade (LIU) and essential component for any foreseen LHC upgrade and could open a way to the future of the accelerator complex. Linac4 will accelerate H-ions from 45keV to 160MeV along the 80m long accelerator. The beam commissioning of the machine has been started with a pre-commissioning on 2011 at the 45keV Low Energy Beam Transport (LEBT) part, progressed to the 107MeV energy after Cell-Couples Drift Tube in the summer 2016 and reached to the final energy at the end of 2016. This presentation will cover the accelerator physics requirements for the CERN accelerator complex and a quick review of Linac4 low, medium and high energy beam commissioning.