As world waits for CERN announcement, Fermilab jumps in

Posted by Emma Woollacott

With scientists at the Large Hadron Collider expected to announce tomorrow that they've found the Higgs boson, the team at the US' Fermilab has made its bid for its share of the glory.

The discovery of the theorized Higgs boson would explain why some particles have mass and others don't. And Fermilab's Tevatron scientists, announcing their final results on the search for the elusive particle, say they've found the strongest indication of its existence yet.

The final analysis doesn't definitely settle the question of whether the Higgs particle exists, but gives what the team describes as a strong hint.

"The Tevatron experiments accomplished the goals that we had set with this data sample," says Fermilab spokesperson Rob Roser. "Our data strongly point toward the existence of the Higgs boson, but it will take results from the experiments at the Large Hadron Collider in Europe to establish a discovery."

The Tevatron results indicate that the Higgs particle, if it exists, has a mass between 115 and 135 GeV/c2, or about 130 times the mass of the proton. This corroborates the Higgs search results that scientists from the Tevatron and the LHC presented at physics conferences in March 2012.

The Tevatron and LHC teams are looking for evidence of the Higgs boson in different ways. The LHC focuses on searching for its decay into two energetic photons, while Tevatron experiments find it easiest to see the decay of a Higgs particle into a pair of bottom quarks.

And the Tevatron team says that the observed Higgs signal in the combined data from the CDF and DZero experiments in the bottom-quark decay mode has a statistical significance of 2.9 sigma. This means there's only a 1-in-550 chance that the signal is due to a statistical fluctuation.

"We achieved a critical step in the search for the Higgs boson," said Dmitri Denisov, DZero cospokesperson and physicist at Fermilab. "While 5-sigma significance is required for a discovery, it seems unlikely that the Tevatron collisions mimicked a Higgs signal."

The team's paper is available here.