New particles made up of four quarks first appear, or help understand how proton neutrons form

The discovery of a new particle consisting of four niobium quarks will be observed for the first time by the agency’s Large Hadron Collider Bottom Quark Experiment (LHCb), according to cern, a finding that will help physicists better understand how quarks “hold together” composite particles such as protons and neutrons and help discover new physics.

New particles made up of four quarks first appear, or help understand how proton neutrons form

A “four quark state” (art figure) consisting of two niquators and two antiquarks. Photo credit: CERN

Quarks are usually in groups of three or two, forming particles called “strongones”. But for decades, theorists predicted the existence of four quarks and five quarks of the strongs, the so-called “tetraquarks” and “pentaquarks”. These four quark states and pentaquark states are called “strange hadchildren”. In recent years, experiments, including LHCb, have confirmed the existence of some of these odd strongchildren, such as the LHCb team at Tsinghua University in 2015, which confirmed for the first time the existence of the “five quark state”.

Scientists believe that the unusual combination of these quarks is an ideal “laboratory” for research, and that in-depth understanding of power is essential to discovering new physics. Strength is a strong interaction that binds protons, neutrons, and nuclei to a close, and is one of the four known basic forces in nature, and the other three basic forces are gravity, electromagnetic and weak forces.

In the latest study, the LHCb team carefully analyzed all the data collected by the LHCb detector during the previous two rounds of the Large Hadron Collider (LHC) and found that the J/ψ particle pair (a J/ψ particle consisted of a niobium quark and a The mass distribution of the antiquark composition) appears to have a “protrusion”, and the statistical significance of the “protrusion” is 5 sigma, reaching the threshold that can be announced to discover new particles, and the mass of the particle indicates that it is composed of four niobium quarks.

Giovanni Pasalowa, a spokesman for the LHCb collaboration group, said: “The particles consisting of four quarks are very peculiar, and the ‘four quark states’ observed so far in experiments such as LHCb contain only two heavy quarks, and our latest discovery is the first particle consisting of four of the same type of heavy quarks, two niquacs and two niobium antiquarks. “

At present, scientists don’t know whether the new particles are “real quark states” — a system of four quarks tightly bound together, or a molecular-like structure that is loosely combined with a pair of two quark particles, but either way, it will help theorists test the theory of strong interactions.