The Large Hadron Collider has been up and running for some time now and scientists are already discoveries that scientists are making. Data obtained with the help of the LHC appears to have proved the existence of pentaquarks (particles formed of five quarks), a particle theorized but never before detected.
According to LHC spokesman Guy Wilkinson, the pentaquark’s discovery is truly remarkable. It doesn’t only represent a new particle, he explains, but it also showcases a unique quark aggregation form in patterns that scientists have never observed before.
Quarks represent those minute ingredients of sub-atomic particles (neutrons and protons). These subatomic particles are made up of three quarks. Four quarks, on the other hand, are found in mesons, which are unstable particles usually found in cosmic rays.
This discovery, Wilkinson explains, was based on an irregularity observed by scientists. In the graph depicting the billions and billions of particle collisions, researchers observed an atypical “bump” which could not have been explained by anything other than a five-quark particle.
LHCb researchers have been examining the decay of the Lambda b baryon as well as three additional particles. With the help of the extremely sensitive detector, they could precisely describe the mass of all decay products. But, surprisingly, they noted that in the production of these decay products, intermediate states were also at play, and these intermediate states indicated the presence of pentaquark particles.
Scientists were the able to understand the precise composition of these pentaquarks. Benefitting from the immense data that the LHC had laid at their disposal, they concluded that the pentaquarks they had discovered were made up of:
- 2 “up” quarks
- 1 “down” quark
- 1 “charm” quark
- 1 “anti-charm” quark
Of course, there is still much to be answered. For one, scientists haven’t yet been able to explain whether these five quarks are all bound together or whether there are two distinct particles, a baryon (made up of 3 quarks) and a meson (made up of 2 quarks) interacting together.
“What we want to do now is to look for other five-quark particles and try and understand more about their nature,” Wilkinson explained.
Scientists are convinced that there is a plethora of pentaquarks to be discovered and studying these unique particles may provide valuable insight.
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