Update: James Gillies, CERN’s spokesperson, is refuting the rumor. The slide in question was “one guy’s speculation,” he says. In fact, CERN is still aiming for collisions in mid-2009, although not at the full design energy of 7 TeV. A full report on the incident is expected soon.

The world’s biggest, newest particle accelerator, the Large Hadron Collider, may be out of service for the entirety of 2009.

The LHC was knocked out of commission earlier this fall, after an electrical fault caused extensive damage to one of its eight sectors. A substantial part of the damage was caused by the liquid helium used to cool the machine, which escaped its cryostat and vaporized—causing an enormous pressure build up.

A couple of blogs have taken note of a presentation given by Jörg Wenninger of the lab’s beam department, in which he apparently claimed the machine may not restart until 2010. That would allow CERN’s accelerator team to install pressure relief valves on the entirety of the LHC machine. 2009 might still be an option, but it would be later in the summer and at lower energies than originally planned.

For my money I’m guessing that most physicists would like to see some collisions next year. Even if they don’t yield new discoveries, they can still be used to calibrate the detectors (and write a few theses).

It should be said that the actual plan is a little unclear. The slide shown here comes from the Resonaances blog, it does not appear in the current online version of Wenninger’s presentation, although there’s a blank page near the bottom where some say it should be.