När smäller LHC? (När startar de upp (igen) egentligen?)

The LHC made it official, and so they will attempt to collide the two proton beams at 3.5 TeV each, on Tuesday March 30.

It’s 01:15am and I just got home after a quite long day of work (although shorter than I expected). Everything needs to be ready before we get collisions, so the efforts have to double. As part of the high level trigger team in CMS, my work this week consists in making sure that we are able to accept all the good collision events (data). After a few days of intensive testing from different groups and people, we hope we will deploy the final version of the trigger “menu” tomorrow, or on Thursday the latest. The high level trigger is a key component of being able to accept data. It is basically a collection of code that runs online, live, to discriminate what information is put into tape and what is not.

It is very likely that we will have lower energy collisions (900 GeV) during the weekend as a preamble for the historic 7 TeV smashings. We also need the trigger to catch beam gas events from 3.5 TeV circulating stable beams (no collisions), maybe on Sunday.

The adrenaline is starting to flow here at CERN. It is somehow difficult to sleep, thinking about all this, for people like me who are on-call. Most of the improvements, fixes, upgrades, etc, that we made after the learning experience of last year’s collisions are now in place, and ready for prime time. We will do just fine. I am sure.