CERN Sets Date for First Attempt at 7 TeV Collisions in LHC


The endcap of the Compact Muon Solenoid (CMS) at the Large Hadron Collider at CERN
The endcap of the Compact Muon Solenoid (CMS) at the Large Hadron Collider at CERN. Courtesy of Arpad Horvath
With beams routinely circulating in the Large Hadron Collider (LHC) at 3.5 TeV, the highest energy yet achieved in a particle accelerator, CERN has set the date for the start of the LHC research program. The first attempt for collisions at 7 TeV (3.5 TeV per beam) is scheduled for March 30, 2010.

“With two beams at 3.5 TeV, we’re on the verge of launching the LHC physics program,” explained CERN’s Director for Accelerators and Technology, Steve Myers. “But, we’ve still got a lot of work to do before collisions. Just lining the beams up is a challenge in itself: it’s a bit like firing needles across the Atlantic and getting them to collide half way.”

Between now and March 30, the LHC team will be working with 3.5 TeV beams to commission the beam control systems and the systems that protect the particle detectors from stray particles. All these systems must be fully commissioned before collisions can begin.

“The LHC is not a turnkey machine,” said CERN Director General Rolf Heuer. “The machine is working well, but we’re still very much in a commissioning phase, and we have to recognize that the first attempt to collide is precisely that. It may take hours or even days to get collisions.”

The last time CERN switched on a major new research machine, the Large Electron Positron collider, LEP, in 1989, it took three days from the first attempt to collide beams to the first recorded collisions.

The current LHC run began on November 20, 2009, with the first circulating beam at 0.45 TeV.  Milestones were quick to follow, with twin circulating beams established by November 23, and a world-record beam energy of 1.18 TeV being set on November 30. By the time the LHC switched off for 2009, on December 16, another record had been set with collisions recorded at 2.36 TeV and significant quantities of data recorded.

Over the 2009 part of the run, each of the LHC’s four major experiments, ALICE, ATLAS, CMS and LHCb recorded over a million particle collisions, which were distributed smoothly for analysis around the world on the LHC computing grid. The first physics papers were soon to follow. After a short technical stop, beams were again circulating on February 28, 2010, and the first acceleration to 3.5 TeV was on March 19.

Once 7 TeV collisions have been established, the plan is to run continuously for a period of 18 to 24 months, with a short technical stop at the end of 2010. This will bring enough data across all the potential discovery areas to firmly establish the LHC as the world’s foremost facility for high-energy particle physics.