In nuclear physics and particle physics, the strong interaction is the mechanism responsible for the strong nuclear force and is one of the four known fundamental interactions. It is essentially responsible for the existence of atomic nuclei consisting of various protons and neutrons. Protons and neutrons are made up of smaller particles, called quarks. And they too are held together by the strong interaction.
Understanding the strong interaction between particles is one of the greatest challenges in nuclear physics today. Experiments to determine the strong interaction are extremely difficult because hyperons are unstable particles that rapidly decompose after production. This difficulty has so far prevented a meaningful comparison between theory and experiment.
Scientists at the Technical University of Munich (TUM) have developed a method to determine the strong interaction with high precision. The measurements are groundbreaking and the key to understanding neutron stars.
The method developed by the scientists has taken a step towards high-precision studies of the dynamics of the strong force in the Large Hadron Collider (LHC).
The story began four years ago. Professor Laura Fabbietti, Professor of Weird and Dense Hadronic Matter at TUM, proposed using a technique called femtoscopy to study the strong interaction in the ALICE experiment. The technique makes it possible to investigate spatial scales close to 1 femtometer (10-15 meters), about the size of a proton, and the spatial range of strong force action.
Using this technique, the scientists were able to study the experimental data for most of the hyperon-nucleon combinations. They also successfully measured the strong interaction for the rarest of all hyperons, the Omega, which consists of three strange quarks. Later, they came up with their framework that can produce theoretical predictions.
Professor Fabbietti said: “My TUM group has opened a new avenue for nuclear physics at the LHC, one that involves all kinds of quarks, achieving unexpected precision in a place no one has looked until now.”
- ALICE Collaboration: Revealing the strong interaction between hadrons at the LHC. Nature, 588, 232–238 (2020) – DOI: 10.1038 / s41586-020-3001-6