A badly soldered electrical connection was likely responsible for the malfunction that put the world's largest particle collider out of action until next year, a senior scientist said Monday.

While it was likely just one poor soldering job out of the Large Hadron Collider's 10,000 connections, "it cost dearly", said Lyn Evans, project leader of the experiment. The particle collider is housed in a 27-kilometre-long tunnel at the European Nuclear Research Organisation (CERN), located near Geneva, Switzerland.

The LHC, built at a cost of $3.8 billion and with a total expected cost of over $9 billion, was officially launched on Sept. 10 when two beams of super-accelerated protons were fired in opposite directions through the 27-km circuit.

The collider is designed to eventually push the protons using a ring of super-cooled magnets to speeds and energies never before reached under controlled conditions, and crash them into one another to create and detect a host of new particles.

But it had to be turned off nine days later after the electrical fault occurred.

Scientists will have to wait a month before officially determining and fixing the problem, as the area where the problem is operates at a temperature near absolute zero and needs to warmed before repair crews can enter.

The super-cold temperatures allow the collider's magnets to be superconductive, making them more energy efficient and capable of pushing the particles at speeds near the speed of light.

It will take another month to cool the magnets down again, meaning the delay will take CERN into an already scheduled winter break, when the machine is powered down to conserve on electricity during the colder months of the year.

The machine is scheduled to start up again in April, but likely won't begin to operate at high energies until May, said Evans.

"It was a hard blow for us," he said.

The collider is expected to be the most powerful tool yet for physicists hoping to uncover the secrets behind the laws of the universe, both on the tiny scale of quantum mechanics and the huge domain of galaxies and black holes.

Once the machine is up and running again, data from the particle collisions will be sent to computer networks around the world, including in Canada, where they will be analyzed to try to reconstruct what happened during these collisions.

Scientists hope the collisions will reveal previously unseen particles and give greater insight into the interactions that occurred during the first few moments of the universe.

One thing in particular they believe they will find is the Higgs boson, a particle thought to impart mass on most other particles. The Higgs boson plays a key role in the standard model of particle physics, a framework that has helped to explain the interactions of particles like electrons, quarks and photons for over 30 years. But so far it has never been found.