SCIENTIFIC EDUCATIONAL CENTER science idea

Predicted by RIKEN researchers, the existence of an exotic particle consisting of six elementary particles known as quarks may deepen the understanding of how quarks combine to form atomic nuclei.
Quarks are the fundamental building blocks of matter. The nuclei of atoms consist of protons and neutrons, which, in turn, consist of three quarks each. Particles consisting of three quarks are collectively known as baryons.
Scientists have long thought about the existence of systems containing two baryons, which are known as dibaryons. In nature, there is only one dibaryon - a deuteron, a hydrogen nucleus consisting of a proton and a neutron, which are very weakly bound to each other. Glimpses of other dibaryons have been found in nuclear physics experiments, but their existence has been very fleeting.
"Although deuteron is the only known stable dibaryon, there may be many more dibaryons," says Takuya Sugiura of RIKEN's Interdisciplinary Program of Theoretical and Mathematical Sciences. "It is important to study which pairs of baryons form dibaryons and which do not, because this provides valuable information about how quarks form matter."
Quantum chromodynamics is a very successful theory describing how quarks interact with each other. But the strong bond that arises between quarks in baryons complicates the calculations of quantum chromodynamics. Calculations become even more complicated when considering bound states of baryons, such as dibaryons.
Now, having calculated the force acting between two baryons, each of which contains three charmed quarks (c-quark, one of the six types of quarks), scientists have predicted the existence of a dibaryon, which they called the charmed di-Omega (charm di-Omega).
For this calculation, the team solved quantum chromodynamics using large-scale numerical calculations. Since a huge number of variables were involved in the calculations, they used two powerful supercomputers: the K computer and the HOKUSAI supercomputer.
"We were very lucky to have access to supercomputers that dramatically reduced the cost and execution time of computing," says Takuya Sugiura. "But it still took us several years to predict the existence of charm di-Omega."
Despite the complexity of calculations, charm di-Omega is the simplest system for studying interactions between baryons.
Researchers are now studying other enchanted hadrons using the Fugaku supercomputer, which is a more powerful successor to the K computer.
"We are particularly interested in interactions between other particles containing charmed quarks," says Takuya Sugiura. "We hope to shed light on the mystery of how quarks combine to form particles, and which particles can exist."
The study was published in Physical Review Letters.
PHOTO: Artist's impression of the recently predicted six-quark state (dibaryon) consisting of two baryons. © Keiko Murano
ab-news.ru (Roman Grigoriev)