In one of the most widely-flagged scientific discoveries in history, CERN scientists have announced that they've finally pinned down the existence of the Higgs boson, with near-certainty.
Physicists working on the CMS and Atlas experiments at the Large Hadron Collider say they've seen a 'bump' in the data indicating the presence of a particle weighing around 125 to 126 GeV.
Both experiments show a level of certainty at the 5 sigma level, equating to a one in 3.5 million chance that the results could have emerged by chance.
"The results are preliminary, but the 5 sigma signal at around 125 GeV we’re seeing is dramatic. This is indeed a new particle. We know it must be a boson and it’s the heaviest boson ever found," says CMS experiment spokesperson Joe Incandela.
"The implications are very significant, and it is precisely for this reason that we must be extremely diligent in all of our studies and cross-checks."
Despite the long wait, the results are still preliminary, with some of the later data still under analysis. Fuller details should emerge later this year.
The Higgs boson has, rather misleadingly, been described as the 'God particle'. The name's intended to reflect its great importance, as its existence could explain why other particles have mass - and therefore how matter as we know it comes to exist.
The Higgs boson was originally proposed in the 1960s by British physicist Peter Higgs as a way of explaining why W and Z bosons alone couldn't account for mass without breaking the Standard Model.
Today's announcement means that physicists can start using the data to learn more about the new particle. It may not, for example, be quite the Higgs boson predicted by physics' Standard Model, but something a little more exotic.
In its basic incarnation, the Higgs boson is the simplest theoretical model that can account for the mass difference between photons and W and Z particles, and for the masses of other fundamental particles.
However, other versions are possible, and could support theories such as supersymmetry, which accounts for the universe's mysterious dark matter. They could also help bear out theories predicting extra dimensions of space - utterly changing our understanding of the universe.
"We have reached a milestone in our understanding of nature," says CERN director general Rolf Heuer.
"The discovery of a particle consistent with the Higgs boson opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle’s properties, and is likely to shed light on other mysteries of our universe."