Lecture II

LHC lay-out C = 26658.90 m Arc = 2452.23 m DS = 2 x 170 m INS = 2 x 269 m Free space for detectors:  23 m

LHC features Technological challenge (+1)

e* = 3.75 10-6 m Bunch spacing 25 ns - 8.3 m

Maximum B-field

Cos(q) coil

Superconducting dipole

Collider luminosity High L needs:

Beam-beam interaction

Head-on collisions

LHC luminosity

LHC insertions 56 m

Beam power density Staged implementation of the collimation system Learning process needed to reach 99.91 % collimation efficiency required at full intensity (~70% efficiency required in the Tevatron) Carbon-carbon collimator ok for phase 1, but insufficient for full intensity Initial LHC luminosity reduced (x 3 ?)

High luminosity experiments

Ion-ion experiment