CERN detects pentaquark particles with LHC

Researchers from one of the experiments at the Large Hadron Collider have discovered a new particle. The existence of this so-called pentaquark particle has been suspected for fifty years, but has not been confirmed experimentally so far.

The preliminary confirmation of the existence of the pentaquark particle was accomplished by scientists at the LHCb experiment, part of the Large Hadron Collider particle accelerator. The pentaquark particles actually comprise a whole family of subatomic particles, just like baryons and mesons. Where baryons, such as protons and neutrons, consist of three quarks, pentaquarks are composed of five particles. The research has yet to be verified by other scientists.

Baryons make up almost all mass in our daily lives and are composed of two quarks and an antiquark. Pentaquarks, on the other hand, only exist for a very short time but are part of the model of quantum chromodynamics. They are predicted by that theory.

Researchers found the pentaquarks, which are made up of four quarks and one antiquark, by looking at the decay of Lambda b baryons with the LHCb detector. In addition to three already known particles, they observed two other masses in the spectrogram. They are caused by a pentaquark, made up of two up quarks, a down quark, a charm quark and an anticharm quark. The researchers will further investigate how the quarks in the pentaquark are interconnected. They may form one superstructure or they may be more connected like meson and baryon.