An artist’s impression of Tcc+, a tetraquark composed of two charm quarks and an up and a down antiquark. Credit: CERN
The graphic, above, and the excerpt, below, are extracted from an article that was recently posted on Physics.org (link also included as "Physics News" in "4 FUN & ENLIGHTENMENT" in the right hand sidebar.
JULY 29, 2021
New exotic matter particle, a tetraquark, discovered
Today, the LHCb experiment at CERN is presenting a new discovery at the European Physical Society Conference on High Energy Physics (EPS-HEP). The new particle discovered by LHCb, labeled as Tcc+, is a tetraquark—an exotic hadron containing two quarks and two antiquarks. It is the longest-lived exotic matter particle ever discovered, and the first to contain two heavy quarks and two light antiquarks.
So have pentaquarks also been observed or are they only a theoretical construct so far?
Posted by: Ole phat stu | August 03, 2021 at 11:06 AM
Stu--My understanding is that researchers have observed "signs" leading to inference of the tetraquark particle family members; but, I am not competent/knowledgeable enough to tell you the actual "signs" that are showing up at the Large Hadron Collider. According to Wikipedia, "LHCb is a specialized b-physics experiment, designed primarily to measure the parameters of CP violation in the interactions of b-hadrons (heavy particles containing a bottom quark)."
Posted by: Cop Car | August 03, 2021 at 04:05 PM