This is news that will delight fans of nuclear physics. Science Alert informs us that the European Laboratory for Particle Physics (CERN) has just announced the discovery of four new subatomic particles at the Large Hadron Collider (LHC) in Geneva.
Note that the world’s largest particle accelerator was created to help researchers find answers to specific questions related to particle physics and cosmology.
Standard particle model tests
To achieve this, the LHC examines the structure of matter at the shortest distances and at the highest energies that have ever been explored in the laboratory. This investigation consists in testing the Standard Model of Particles, which is our most common theory of nature.
Remember that the Higgs boson is one of the particles whose existence has been confirmed thanks to the LHC. It is an elementary particle that forms one of the most important elements of the Standard Model of particle physics.
A powerful force that is different from electromagnetism
According to the theory of strong interaction, also known as “quantum chromodynamics”, the atomic nucleus consists of protons and neutrons. These each have three small particles called quarks. This theory also describes the way in which the latter interact through the strong force by exchanging particles called gluons. However, the way gluons behave with quarks creates a powerful force, the behavior of which is very different from that of electromagnetism.
Theoretical construction in elementary particle physics that describes bosons, the electromagnetic and strong interaction of all elementary particles. Image credit: Shutterstock / ShadeDesign
At the time of the quark discovery, researchers had already proposed the possibility of several combinations, at least in theory. The theory mentioned, among other things, pairs of quarks and antiquarks (mesons), three quarks (baryons), three antiquarks (antibaryons), two quarks and two antiquarks (tetraquarks) as well as four quarks and one antiquark (pentaquarks). It is worth remembering that the existence of pentaquarks was also confirmed in 2015 thanks to the CERN particle accelerator.
The four new particles that have just been discovered are all tetraquarks with a pair of charm quarks and two more quarks. Like the proton and the neutron, these are all particles although they are not fundamental particles. In total, the Large Hadron Collider found 59 new hadrons. Discoveries designed to enable researchers to better understand the secrets of the universe.