The Higgs particle just got a bit lighter, and the race to find it a little tighter, thanks to the most precise measurement yet of the mass of the W boson.
Physicists at the Collider Detector at Fermilab (CDF) near Chicago announced on Monday that the W boson - one of the particles that mediate the weak nuclear force - has a mass of 80.413 gigaelectronvolts (GeV).
reposted from: New Scientist 13 January 2007
my highlights / emphasis / edits
The standard model of particle physics links the masses of W boson, the "top" quark and the Higgs boson. Using the newly measured mass of the W and the already well-known mass of the top quark, the team recalculated the predicted mass of the elusive Higgs, which is thought to give all other particles their mass. The upper limit for the mass of the Higgs is now 153 GeV, down from the previous limit of 166 GeV.
Physicists already know that the Higgs is heavier than 114 GeV, because searches up to that energy have found nothing.
Until now, the Large Hadron Collider at CERN near Geneva, due to start working later this year, was the firm favourite to find the Higgs. But the lighter Higgs is well within the range of the Tevatron collider running at Fermilab. "For us at the Tevatron and CDF, it is very good news," says Mark Lancaster, CDF team member at University College London.
If the colliders do not find the Higgs at these energies, physicists will be forced to look beyond the standard model.
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