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Fermilab ‘closing in’ on the God particle

The US particle accelerator now has a 50% chance of seeing the Higgs boson ahead of Europe's Large Hadron Collider, say scientists

Scientists with the Fermi National Accelerator Laboratory, Illinois, home of the Tevatron particle accelerator, say their ageing machine now stands at least a 50% chance of spotting the elusive Higgs boson by the end of next year.

The estimate is based on the accelerator鈥檚 efficiency at producing high energy particle collisions, now running at an all-time high, and the chances that the Higgs鈥 mass falls within a range detectable at Fermilab.

With CERN鈥檚 malfunctioning Large Hadron Collider (LHC) more than six months away from restarting, and another year or more from releasing data, it looks increasingly likely that the Tevatron will have a clear run at being the first to spot the Higgs.

Not a race?

鈥淲e鈥檙e not racing CERN,鈥 says Fermilab director, Pier Oddone, who points out that many physicists working at the Tevatron are also heavily involved with the LHC. However, other scientists at Fermilab told New Scientist that the sense of competition is real, and that researchers are 鈥渨orking their tails off鈥 analysing data from the Tevatron鈥檚 two key particle experiments, named and .

鈥淚ndirectly, we鈥檙e helping them,鈥 says DZero spokesman Dmitri Denisov of his European counterparts. 鈥淭hey鈥檙e definitely feeling the heat and working a little harder.鈥

Past experiments and theoretical models predict that the Higgs boson, widely thought to be the last undiscovered particle, in the so-called Standard Model of particle physics has a mass that is equivalent to a value between 114 and 184 GeV (billion electron Volts). This range falls within Tevatron鈥檚 sensitivity, which suggests that if the Higgs is real, it will only be a matter of time before it turns up at Fermilab.

Growing possibility

But that window inside which the Higgs could exist is shrinking, in a way that favours the Tevatron.

Last summer data released by both CDF and DZero effectively excluded a value of 170 GeV, where a Higgs boson would stand out particularly well against the background noise of other particle interactions. Data gathered since then is continuing to expand the possibility for detections on either side of this value.

That means the closer the Higgs mass is to 170 GeV, the greater the chances are that it will be seen first at Fermilab.

Denisov estimates that evidence for a 150 GeV Higgs boson could emerge as early as this summer, well before the LHC is even projected to restart after it was damaged last year. Alternatively, if the Higgs mass is 120 GeV, it would likely be the end of 2010 before scientists at the Tevatron were confident enough to report a detection.

Clear signal

One thing that will aid physicists is the fact that the Tevatron collides protons with anti-protons. The resulting collisions create less background noise than the proton-proton collisions at LHC are expected to produce.

鈥淲e couldn鈥檛 be in a better position,鈥 says Jacobo Konigsberg, a physicist at the University of Florida, Gainesville, who is co-spokesman for the CDF experiment. 鈥淭he Tevatron is working beautifully and in the next two years we could double the data taken during the last eight.鈥

Topics: Large Hadron Collider / Particle physics / Quantum science