Cern scientists reporting from the Large Hadron Collider (LHC) have claimed the discovery of a new particle consistent with the Higgs boson.
The discovery has been the subject of a 45 year hunt to explain how matter attains its mass.
Both of the Higgs boson hunting experiments at the LHC have seen a statistical level of certainty in their data worthy of a “discovery”.
More work will be needed to be certain that what they see is a Higgs, however.
The results announced at Cern (European Organization for Nuclear Research), home of the LHC in Geneva, were met with loud applause and cheering.
Prof Peter Higgs, after whom the particle is named, wiped a tear from his eye as the teams finished their presentations in the Cern auditorium.
“I would like to add my congratulations to everyone involved in this achievement,” he added later. “It’s really an incredible thing that it’s happened in my lifetime.”
The team claimed they had seen a “bump” in their data corresponding to a particle weighing in at 125.3 gigaelectronvolts (GeV) – about 133 times heavier than the protons that lie at the heart of every atom.
They claimed that by combining two data sets, they had attained a confidence level just at the “five-sigma” point – about a one-in-3.5 million chance that the signal they see would appear if there were no Higgs particle.
However, a full combination of the CMS data brings that number just back to 4.9 sigma – a one-in-two million chance. For the scientists to be certain of their discovery they would need a calculation of 5.0 sigma.
Prof Rolf Heuer, director-general of Cern, commented: “As a layman I would now say I think we have it. It is a historic milestone but it is only the beginning.”
A confirmation that this is the Higgs boson would be one of the biggest scientific discoveries of the century; the hunt for the Higgs has been compared by some physicists to the Apollo programme that reached the Moon in the 1960s.
Scientists would then have to assess whether the particle they see behaves like the version of the Higgs particle predicted by the Standard Model, the current best theory to explain how the Universe works. However, it might also be something more exotic.
All the matter we can see appears to comprise just 4% of the Universe, the rest being made up by mysterious dark matter and dark energy.