Called the Higgs boson, the theoretical particle has been long sought by physicists who think it's responsible for all mass in the universe—hence the name God particle.

It's also one of the targets of experiments by the Large Hadron Collider (LHC), which began smashing subatomic particles together at half its maximum power in March.

According to the widely accepted standard model of physics, all particles acquire their mass by interacting with the Higgs boson.

But some theories say that the Higgs boson is not one, but multiple, particles with similar masses but different electrical charges.

Now, researchers at Fermilab in Batavia,