Measurement of the Z boson cross-section in - Harvard University ...

Chapter 2
The Accelerator and the
Experiment
2.1 The Large Hadron Collider
The Large Hadron Collider (LHC) is located partly in Switzerland and partly
in France. It has been built and is managed by the European Council for Nuclear
Research (CERN). It is a proton synchrotron, designed to collide protons with protons
at a maximum center-of-mass energy of 14 TeV and a peak instantaneous luminosity
in excess of 10 34 protons cm −2 s −1 . The LHC is housed in the 26.7 km circumference
tunnel that formerly contained the Large Electron Positron (LEP) collider.
A schematic view of the CERN accelerator complex is shown in Figure 2.1. Proton
acceleration occurs in several different stages in this complex. The protons are ini-
tially obtained by ionizing gaseous hydrogen. They are accelerated in bunches in the
linear accelerator (LINAC2) to an energy of 50 MeV. The following stage, the Pro-
ton Synchrotron Booster (PSB), boosts them up to 1.4 GeV, after which the Proton
Synchrotron (PS) accelerates them to 26 GeV. The proton bunches are then injected
into the Super Proton Synchrotron (SPS), which accelerates them to 450 GeV and
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