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A mid-term report for LS1

As the LHC’s first long shutdown, LS1, enters its second calendar year, it’s a good time for a mid-term report on how things are progressing


Towards the end of last year, I had the pleasure to go down to the Large Hadron Collider (LHC) tunnel to witness the closure of the first of the machine’s sectors to be completed. As I write, three sectors are now closed up, with a fourth not far behind. These are important milestones, and you can follow progress in detail in the regular LS1 reports. They show that we’re on schedule for physics to resume in about a year from now, but more than that, they are an important reminder of the LS1 motto: safety, quality, schedule.

It is fantastic news that we are on schedule, and testimony to the rigour that went into the detailed and complex planning of all the work that had to be undertaken in LS1. But more important than the schedule is the fact that we’ve carried out the work safely and that the quality of the work underground and throughout the accelerator chain is first class, as quality assurance tests are showing. That in turn is testimony to the calibre of the CERN personnel working alongside teams from Greece, Pakistan, Poland and, earlier in the process, JINR Dubna. My thanks go to them.

As we enter 2014, what does the restart schedule look like? Starting with the injector chain, access systems will start to be recommissioned as of next month, with powering beginning in April and beam tests starting in late spring and early summer for the Proton Synchrotron complex. Moving through the accelerator chain, the Super Proton Synchrotron should be ready for physics to resume in October.

As for the LHC, with pressure tests now successfully under way, we will soon be starting the cool-down, beginning with sector 6-7 in May. By the end of October, the whole LHC ring is scheduled to be at its operating temperature of 1.9 K. Power testing should be complete by the end of the year, allowing an early start for LHC physics in 2015. So the mid-term report is a good one: safe, carried out to the highest quality and so far right on schedule. There’s a long way to go, however, and much could still happen, but we can be satisfied with progress to date.