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New Delhi: A new class of sub-atomic particles known as pentaquarks has been discovered by scientists at the European Organization for Nuclear Research, better known by its French acronym CERN, in Geneva.

The discovery was reported on Tuesday by scientists who are part of LHCb, one of the units at the Large Hadron Collider (LHC).

The discovery confirms the existence of particles indicated in a model proposed more than 50-years ago by American physicist Murray Gell-Mann.

According to Gell-Mann, a category of particles known as baryons (in the nucleus of an atom), are made of of three charged objects called quarks, and another category of particles (also in the nucleus), mesons, are made of quark-antiquark pairs. Gell-Mann was awarded the Nobel prize in physics for this work in 1969.

A pentaquark, as the name suggests, consists of four quarks and an antiquark.

“The pentaquark is not just any new particle," LHCb spokesperson Guy Wilkinson said in a press release. “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," he added.

“Studying its properties will allow us to understand better how ordinary matter, the protons and neutrons from which we’re all made, is constituted," said Wilkinson.

Although several attempts have been made over decades, this is the first time that conclusive evidence of pentaquarks has been found. The LHCb team has submitted a paper reporting the findings to the journal Physical Review Letters.

“Benefiting from the large data set provided by the LHC, and the excellent precision of our detector, we have examined all possibilities for these signals, and conclude that they can only be explained by pentaquark states," said LHCb physicist Tomasz Skwarnicki of Syracuse University in a press release.

The next step, according to CERN scientists, will be to study how the quarks are bound together within the pentaquarks. “The quarks could be tightly bound," said LHCb physicist Liming Zhang of Tsinghua University, “or they could be loosely bound in a sort of meson-baryon molecule, in which the meson and baryon feel a residual strong force similar to the one binding protons and neutrons to form nuclei."

The LHC was instrumental in the discovery of the Higgs Boson, a subatomic particle, in 2013.

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