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Rhythm of life to change at Cern (photo: Cern team watching low energy first collisions 16 December 2009 at 04:00)

Update 22:50  Geneva, Switzerland (GenevaLunch) – The annual shutdown of accelerators at Cern, long a part of the rhythm of the European Organization for Nuclear Research, are coming to an end, with the LHC (Large Hadron Collider) gearing up. The organization will instead continue to operate the LHC for 18-24 months, then close for a longer period, possibly a year, to accommodate the LHC’s needs at a higher energy, Cern said 10 March, confirming information it  provided in February, that the LHC would shut down in 2011.

The LHC is a particle accelerator used by physicists to study the smallest known particles: the fundamental building blocks of all things.

“Traditionally, Cern has operated its accelerators on an annual cycle, running for seven to eight months with a four to five month shutdown each year,” Cern said in a Wednesday press release. “With the LHC, things are different. Being a cryogenic machine operating at very low temperature, the LHC takes about a month to bring up to room temperature and another month to cool down. A four-month shutdown as part of an annual cycle no longer makes sense for such a machine.”

The beauty of a collision: first proton-proton collisions, Cern, 16 December 2009

An earlier plan was for the machine to be geared up from the start to operate at its design energy of 14 TeV, but after Cern was forced to shut down the LHC just days after it started operation in September 2008 it became apparent that the complexity of gearing the LHC up to run at 14 TeV would eliminate the possibility of doing “first physics” experiments.

In 2009 Cern opted to run the LHC first at half-energy to focus on providing collisions in 2010 for first physics experiments.

A factor in past annual closings has been local electricity agreements: Cern uses 230 megawatts of electricity with the LHC running. The LHC alone consumes 120 megawatts of electricity, roughly half the consumption of the canton of Geneva. Cern is on the border between France and Switzerland, and it has two substations, one in each country, and contracts with Swiss and French suppliers. In summer, Cern is supplied by relatively cheap electricity from France, the source of which is mostly nuclear. Since the supply of nuclear-sourced electricity is inelastic, because it is impossible to add additional capacity to a nuclear power plant, EDF, the French electricity supplier, reduces electricity to Cern if it needs to, in a hurry, in return for good electricity rates.

The LHC will start, within weeks, to collide beams at 7 TeV, some 3.5 times higher than Fermilab’s Tevatron, Cern confirmed Wednesdady 10 March. Once it has operated at that energy, for several months, it will be shut down for several months to prepare it to operate at 14 TeV, its design energy.

Cern interview with Rolf Heuer, director general of Cern, on the implications for physics worldwide of the LHC’s current work, with examples

Background, GenevaLunch

Links to other sites: BBC, Ria Novosti news agency