Exotic particle packs a foursome of quarks | Science News

ADVERTISEMENT

SUPPORT SCIENCE NEWS

Science News is a nonprofit.

Help us keep you informed.


News

Exotic particle packs a foursome of quarks

Tetraquarks could help physicists understand the universe’s first generations of matter

By
3:37pm, April 11, 2014

The rediscovery of an exotic particle provides the best evidence yet that quartets of quarks exist in a universe dominated by two- and three-quark matter.

By validating the particle’s existence, says lead author Tomasz Skwarnicki, a physicist at Syracuse University in New York, “we are automatically proving that four-quark states exist.”

Quarks, one of the fundamental constituents of matter, never exist on their own. Held together by particles called gluons, quarks and their antimatter counterparts, antiquarks, cluster in threes to form baryons (including protons and neutrons) and in pairs to produce mesons (including pions and kaons).

But in 2003, physicists at the Belle particle collider in Japan discovered a bizarre particle called X(3872) that didn’t seem to fit in either category. Based on its mass (3,872 million electron volts) and the particles it decayed into, X(3872) appeared to consist of a charm quark, an anticharm and at least

This article is only available to Science News subscribers. Already a subscriber? Log in now. Or subscribe today for full access.

Get Science News headlines by e-mail.

More Particle Physics articles

From the Nature Index Paid Content