The present status of LHC

The Large Hadron Collider (LHC) project was approved by the CERN Council in December 1994. The machine will provide proton-proton collisions with a centre of mass energy of 14 TeV and an unprecedented luminosity of 10³⁴ cm^-2s^-1. In order to achieve the design energy within the constraint of the 27 km circumference LEP tunnel, the magnet system must operate in superfluid helium below 2 K, with a dipole field of 8.4 Tesla. In addition, space limitations in the tunnel as well as cost considerations dictate a two-in-one magnet design, where the two rings are incorporated into the same cryostat. The machine will also provide heavy (Pb) ion collisions with a luminosity of 10²⁷ cm^-2s^-1 using the existing CERN ion facility. Space will be kept above the LHC for the eventual reinstallation of components of the LEP machine to provide future e-p collisions if the physics case justifies it