4th report from the LHC performance workshop

On a relatively warm Thursday morning in Chamonix (-7 Celsius) the workshop looked at what things would be like after the upcoming long shutdown (LS1 -  2013/14). A large number of re-training  quenches of the LHC dipoles will be required in order to reach the nominal energy of 7 TeV so the beam energy in the first years after LS1 is expected to be around 6.5 TeV. The planned injector upgrades will not have been deployed at this stage, but the injector performance still looks capable of supplying sufficient beam quality to enable the LHC to reach the design luminosity of 1x10³⁴ cm^-2s^-1.

A lot has been learned operating at 3.5 TeV over the last couple of years and many improvements have been made in the magnet powering and protection systems. The prospects for post-LS1 machine availability are encouraging. Potential limitations to post-LS1 performance (quenches, radiation to electronics, UFOs) were also considered.

The evening was spent considering the more dim and distant future and the prospects for the LHC Injector Upgrade project and its client, the High-Luminosity LHC (HL-LHC), tentatively scheduled to start operating around 2023. The goals of the HL-LHC are ambitious (200 - 300 inverse femtobarns per year) and the demands on the upgraded injectors reflect this. The devil is in the detail but it's clear a lot of work remains to be done.

by Bulletin's correspondent from Chamonix