Particle physics Researchers decode newly discovered particles for the first time at Cern
A research team has used the Geneva particle accelerator to precisely measure the properties of "all-charm tetraquarks" for the first time. This exotic particle discovered at Cern near Geneva was presented for the first time at a specialist conference in 2020.
03.12.2025, 17:00
SDA
The results, published on Wednesday in the scientific journal Nature, represent a further step towards a deeper understanding of the fundamental building blocks of the universe. Because "all-charm tetraquarks" consist of the elementary particles quarks.
Elementary particles are the smallest building blocks of everything that exists. They are the building blocks of matter that cannot be broken down any further. They form the basis for all other particles and therefore for all matter in the universe. While in our everyday lives we often deal with large objects that are made up of many small particles, such as atoms, the world of elementary particles consists of much smaller units.
Quarks are the building blocks of protons and neutrons, which together form the atomic nucleus. In protons and neutrons, quarks typically occur in combinations of three. There are also short-lived mesons consisting of a quark and an antiquark.
So much for the classical inventory as it appeared until a few years ago. In recent years, however, physicists have detected even more combinations of quarks in particle accelerators. These include the "all-charm tetraquarks", which consist of two heavy charm quarks and two lighter antiquarks.
Results shed light on new particle
The results of the current study shed new light on these exotic particles. Using the Large Hadron Collider (LHC) at the European Nuclear Research Center Cern, the researchers measured some important properties of the particles, which are known as quantum numbers. These include the so-called spin and symmetry properties.
The results indicate that these exotic tetraquarks are strongly bound, rather than loosely bound like molecules. This gives the scientists important clues about the internal structure of these particles.
According to the researchers, the results will now be used to test theories about the forces that hold protons and neutrons together.
The research was carried out by Cern's CMS collaboration team, which involved over 200 research institutions from around the world.
