Scientists at CERN in Switzerland have discovered a new category of subatomic particles named pentaquarks. The research has succeeded in solving the mystery pertaining to the particle in question. The results might also shed more light on the formation of matter. The findings might soon be published in the journal Physical Review Letters.
One possible layout of quarks in a pentaquark particle.
The existence of the pentaquark was suspected by scientists back in the 1960s. Unfortunately, it was never observed. Until now.
Quarks make up composite subatomic particles. The latter are categorised as per the number of quarks they consist of. For instance, proton and neutrons are made up of three quarks, classified as baryons. Now, a particle made of five quarks – a pentaquark – has been shown to exist.
“The pentaquark is not just any new particle,” CERN spokesperson Guy Wilkinson said in a statement. “It represents a way to aggregate quarks, namely the fundamental constituents of ordinary protons and neutrons, in a pattern that has never been observed before in over 50 years of experimental searches.”
The existence of the particle has been demonstrated thanks to the powerful LHCb experiment.
Physicists were examining the decay of a baryon called Lamda b into three other particles when their attention was caught by the pentaquarks. For the first time in the history of science, they observed a transition state whereby two unknown particles [Pc(4450)+ and Pc(4380)+] were seen. Upon studying the mass of these new particles, the researchers concluded that they were in pentquark states.
“More precisely, the states must be formed of two up quarks, one down quark, one charm quark, and one anti-charm quark,” said LHCb physicist Tomasz Skwarnicki.
More data was generated by the LHCb and their explanation was confirmed.
“It’s as if the previous searches were looking for silhouettes in the dark, whereas LHCb conducted the search with the lights on, and from all angles,” the CERN release explains.
“Studying [the pentaquarks] properties may allow us to understand better how ordinary matter, the protons and neutrons from which we’re all made, is constituted,” said Wilkinson.