Wednesday, April 6, 2011

Physicists Found New Particle

Physicists at the Fermi National Accelerator Laboratory are planning to announce Wednesday that they have found a suspicious bump in their data that could be evidence of a new elementary particle or even, some say, a new force of nature. The results, if they hold up, could be a spectacular last hurrah for Fermilab’s Tevatron, once the world’s most powerful particle accelerator and now slated to go dark forever in September or earlier, whenever Fermilab runs out of money to operate it.

One possible explanation for this mysterious bump, scientists say, is that it is evidence of a new and unexpected version of the long-sought Higgs boson. This is a hypothetical elementary particle that, according to the reigning theory known as the Standard Model, is responsible for endowing other elementary particles with mass. Another explanation might be that it is evidence of a new force of nature — in addition to gravity, electromagnetism, and the strong and weak nuclear forces we already know and are baffled by — that would manifest itself only at very short distances like those that rule inside the atomic nucleus. Either could shake what has passed for conventional wisdom in physics for the last few decades. Or it could be there is something they do not understand about so-called regular physics.

Physicists outside the Fermilab circle said they regarded the results, which have been widely discussed in physics circles for several months, with a mixture of awe and skepticism. The Tevatron has been colliding beams of protons and their opposites, antiprotons, that have been accelerated to energies of one trillion electron volts, for more than two decades looking for new forces and particles. The new particle showed up in an analysis of some 10,000 of those collisions collected by the Collider Detector at Fermilab, one of two mammoth detectors at the facility, which is outside Chicago.