Geneva  - A giant particle accelerator intended to provide clues as to how the universe began has been shut down for two months because of a fault, its operators said Saturday.

The move came after helium leaked into the tunnel of the Large Hadron Collider on Friday afternoon, according to a statement released by European Organization for Nuclear Research (CERN).

Preliminary investigations indicate that the most likely cause of the problem was a faulty electrical connection between two super- cooled magnets, which probably melted at high current leading to mechanical failure.

The sector of the ring-shaped tunnel that was damaged has to be warmed up well above absolute zero so that repairs could be made, a process which will take about two months, CERN said.

The 6.6-billion-dollar experiment, which began on September 10, was halted last weekend, but restarted again on Friday when a beam of protons were sent racing around the tunnel at high speed.

It was then that the leak was discovered.

The tunnel, with a circumference of 27 kilometres, is located 90 metres under the Swiss French border near Geneva.

The idea is to create conditions believed to be similar to those moments after the Big Bang which most physicists believe to have been the origin of the universe.

Scientists hope the tests will shed light on why there is around five times as much mysterious dark matter than visible matter present in the universe.

The so-called Big Bang Day, when two proton beams will go onto a pre-set course for a massive collision, is not expected to occur for a year or so.

When Big Bang Day arrives, two proton beams will be steered in opposite directions around the collider at close to the speed of light, completing about 11,000 laps per second. (dpa)