So as you may well be aware, the LHC started up again this weekend after a good 14 months off.
September 10th last year was the date penned for the long overdue startup of the Large Hadron Collider – the worlds biggest (and best) particle accelerator. Unfortunately a problem with the cooling system caused a leak of liquid helium and a saftey mechanism called a quench kicked it. It basically ruined a few magnets so the whole thing had to be shut down to be fixed.
Well, it was fixed, and this weekend saw the grand reopening. On Friday evening, the various LHC control rooms were full of physicists and excitement as the beams were reinjected into the machine. First one way around, then the other. The plan, as us postgrads understood it, was that collisions (ie, two beams in the LHC going in opposite directions and brought to a focus at the detectors) were not due until early December.
Well, we were wrong. Today (the 23rd November), the LHC injected beam 1 into the LHC, then injected beam 2 and started ‘beam synchronization’. I don’t fully understand what that means, but I know that there was one bunch per beam (about a metre in length worth of protons), and my best guess at ‘beam synchronization’ is that the two bunches were brought close together.
Obviously the beams weren’t focussed and we weren’t running at anything close to design luminosity, but a few collisions occured in all 4 detectors. An exciting moment for everyone involved with the LHC, indeed.
The CERN Press Release of the weekend’s events and a summary of the collisions explains a bit further what the goings on were this weekend, and what the plans for the LHCs immediate future are.
The coming months should be an exciting time for particle physics, and the coming years will hopefully shed some light on the darker corners of the Standard Model and beyond…
