CERN Operations Group leader Mike Lamont (foreground) and LHC engineer in charge Alick Macpherson in the CERN Control Centre early this morning.
In the early hours of this morning, the beam energy was ramped up to 3.5 TeV, a new world record and the highest energy for this year’s run. Now operators will prepare the machine to make high-energy collisions later this month.
At 5:23 this morning, Friday 19 March, the energy of both beams in the LHC was ramped up to 3.5 TeV, a new world record. During the night, operators had tested the performance of the whole machine with two so-called ‘dry runs’, that is, without beams. Given the good overall response, beams were injected at around 3:00 a.m. and stabilized soon after. The ramp started at around 4:10 and lasted about one hour.
In my message this week, I’d like to congratulate the LHC team on accelerating two beams to 3.5 TeV in the early hours of this morning. The timing could not have been better. Coming during a week of CERN Council meetings, it allowed us to show delegates the great progress we’re making.
The occasion also gave us the opportunity to set out again the prudent step-by-step approach that we’re taking to get the LHC up and running, and it was refreshing to hear one member of the Scientific Policy Committee declare on Monday that we should never forget that the LHC is not a turnkey machine.With the progress the LHC is making, that simple fact would be easy to overlook. The figures coming back from this first run are already quite remarkable. In Week 10, the LHC’s availability for the operators was over 65%: it usually takes a new accelerator years to reach that level. And over the last few weeks, operation of the LHC at 450 GeV has become routinely reproducible, which is again a feat that usually takes a new machine much longer to achieve.
Over the last couple of weeks, operation of the LHC at 450 GeV has become routinely reproducible. The operators were able to test and optimize the beam orbit, the beam collimation, the injection and extraction phases as well as the associated protection system. On 12 March, both beams were ramped up to 1.18 TeV. The overall response from the machine was very positive.
The first part of this week saw a technical stop, during which the magnet and magnet protection experts continued their campaign to commission the machine to 6 kAmps – the current needed to operate at 3.5 TeV per beam. Tests are still ongoing to fully understand the electrical behaviour of the dipole circuits with currents higher than 2 kAmps, which has an impact on the quench protection system (see box) and on the procedure for ramping the beam energy to 3.5 TeV (6kAmps).
While the experts are working to fully understand the circuit performance (for details, watch the embedded video interview with Andrzej Siemko, Group Leader of the LHC machine protection), the operators will continue ramping the beam energy and prepare for high-energy collisions later this month.