Higgs boson: Team head Lyn Evans tells of shock at find
The Welsh head of the project searching for the so-called God particle admits he is in shock over a dramatic find which may end the 45-year hunt.
Aberdare-born Dr Lyn Evans told BBC Wales scientists in Geneva are "99.999%" certain they have found the Higgs boson.
"We have discovered what makes matter, at last," said Dr Evans, head of the CERN Hadron Collider project.
But he said more work is needed to "nail down" proof it is the Higgs.
The results announced at Cern, home of the Large Hadron Collider (LHC) in Geneva, on Wednesday were met with loud applause and cheering.
Peter Higgs, after whom the particle is named, wiped a tear from his eye as the teams finished their presentations in the Cern auditorium.
Dr Evans said: "Suffice to say this is very important. It's how nature works at its most fundamental level.
"A huge piece of the jigsaw of how nature works has been put in place today. The Higgs has got to be positively identified. Its spin has to be measured by taking much more data.
'Voyage of discovery'
"We need to take much more data to really nail down all the quantities - and then we're into a voyage of discovery."
Dr Evans, who studied physics at what was then the University of Wales, Swansea, completed a PhD in 1970, said now that the Higgs boson had been all but identified "many more questions can be answered".
He said: "We know the origin of mass. The next question is what is dark matter, that's the next step."
Dr Evans became leader of the project in 1994 and has dedicated the past 16 years of his career to finding the particle.
The LHC smashes together protons to simulate the conditions immediately after the Big Bang, which is thought to have been the moment the universe came into being.
It took 10,000 scientists a total of 14 years to assemble the ring-shaped tunnel below the Swiss and French border.
It is 100m underground with a circumference of 27km.
"Quite frankly, I'm still in a bit of shock," said Dr Evans.
"I did not expect it to come out so clearly.
"The atmosphere in the seminar was incredible, it was very emotional."
Dr Evans tipped Peter Higgs to receive the Nobel prize for his pioneering work in partical physics.
"That's really is something for British science. The UK's contribution to this has been enormous," he said.