The pentaquark is made up of five smaller entities, four quarks and an anti-quark. “More precisely the states must be formed of two up quarks, one down quark, one charm quark and one anti-charm quark.”
The team has identified the existence of the peantaquark by watching for the decay of a baryon known as Lambda b. As it split up into three well-known particles—well known to physicists at least: a J-psi, a proton and a charged kaon, if you’re keeping track—the scientists observed a transition state in which two previously unobserved particles could be identified.
http://press.web.cern.ch/press-releases/2015/07/cerns-lhcb-experiment-reports-observation-exotic-pentaquark-particles
