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Large Hadron Collider in multi-magnet quench hiccup

First 2010 beams delayed as new redline painted on dial

A technical hiccup has delayed the planned restart of the Large Hadron Collider (LHC), the titanic subterranean magno-doughnut particle smasher situated deep beneath the Franco-Swiss border.

The LHC, most outrageous matter-rending machine ever assembled by the human race, had been expected to fire up its circulating hadron beams once more following the Xmas break today. However last night an "over enthusiastic" automatic protection system cut in, causing some fifty of the mighty collider's huge superconducting magnets to "quench".

A quench occurs unpredictably when the magnets get warmer than 9.6 degrees above absolute zero, causing their superconducting properties to disappear and their powerful fields, necessary to bend hyperpowered lightspeed particle beams around into a circle, to collapse. Normally the magnets are kept chilled down to a frosty 1.9 degrees using liquid helium.

Should a quench occur with full-power beams up and circulating, the result would be disastrous as the released, uncontrolled bolts of high-energy protons would deliver a blast equivalent to being rammed by an aircraft carrier. However there are automatic "beam dump" systems to cope with this, where the rays are quickly fired into special cooled, shielded graphite absorbers before temperatures can climb too high.

But quenching magnets will also damage themselves without help from the beams, and in some circumstances need to be rapidly warmed up to prevent this. The finishing touches were put on a new Quench Protection System (nQPS) while the LHC was shut down for Xmas, able to automatically fire up rapid-acting heaters if a quench is detected.

Last night, it seems that a false alert within the nQPS triggered fifty of these heaters, causing the affected magnets to quench abruptly.

"The quenching is not so dangerous in itself but it does unnecessarily stress the system," commented CERN boffins - though presumably it would have caused an abrupt dump incident had a powerful beam been circulating.

For now, a limitation of 2000 amps current in the electrical connections which set off the nQPS has been imposed, which will prevent the jumpy heaters from triggering again.

"We will carry on the beam commissioning program as planned with the above limitation in place for the moment. Still hope to put beam in tomorrow," control-room scientists said.

The LHC's operators hope to crank it up to half its designed maximum power this year, with beams at 3.5 tera-electron-volts - already by far the most powerful ever collided. After a lengthy period of matter-wrangling at this strength, further mods will be carried out before escalating to a still more punishing 7 TeV.

Such brutal treatment is expected to force tortured hadrons to cough up many of the universe's secrets. In particular, visitors from other dimensions (albeit extremely small and shortlived ones) may be on the cards. ®

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