Closing in on the Higgs particle

While major repairs continue at Europe's broken particle collider in Switzerland, scientists at Fermilab near Chicago are cornering the elusive God particle
Simulated trace of a Higgs boson
Simulated trace of a Higgs boson. Photograph: Fermilab

This is turning out to be quite a race.

It is more than 40 years since the Edinburgh-based physicist Peter Higgs and other scientists came up with the idea that an invisible field permeates space and confers mass on elementary particles, such as the quarks that make up protons and neutrons in atomic nuclei, and leptons like the electron that form clouds around the nucleus and keep atoms electrically neutral.

Just as a photon is a particle of light, the Higgs boson is a particle associated with what has come to be known as the Higgs field. Without the field, the basic building blocks of nature would have no mass, and so the matter we see today that makes up planets, stars and even us, would not exist.

In the 1990s, scientists at Cern working with an older particle collider called LEP searched long and hard for the Higgs boson. They ruled out a wide range of masses that the particle could have, and may have seen a glimpse of it before the machine shut down to make way for the Large Hadron Collider.

When LEP closed at the end of 2000, scientists knew the Higgs particle must weigh more than 114GeV, where 1 gigaelectron volt (GeV) is something like 1/6000 billion billion grams.

Finding the Higgs particle could be the first major discovery in 21st century physics, but Cern is not the only lab looking for it. We've just had news that scientists working on Fermilab's Tevatron – the most powerful working particle collider in the world – are closing in on the Higgs.

Their latest hunt has ruled out a Higgs particle between 160 and 170GeV, meaning the particle is now expected to be found somewhere within two windows: 114GeV to 159GeV and 171GeV to 185GeV. The hunt goes on, and the longer it takes Cern to get the Large Hadron Collider up and running, the better Fermilab's chances of taking the prize.

In a statement put out by the lab, Robert Roser, a co-spokesman for one of the detectors on the experiment, said:

A particle collision at the Tevatron collider can produce a Higgs boson in many different ways, and the Higgs particle can then decay into various particles. Each experiment examines more and more possibilities. Combining all of them, we hope to see a first hint of the Higgs particle.

So perhaps we won't have much longer to wait. The nature of the Higgs, when and if it is discovered, will hopefully open the door to a new era of physics.