Physicists have described the influence of correlated pairs of nucleons on the distribution of quarks and gluons inside atomic nuclei. The scientists used data from high-energy experiments and showed how pair bonds between protons and neutrons inside nuclei change their structure at the parton level. The work was published in the journal Physical Review Letters.
Physicists have been studying the structure of atomic nuclei for decades, where the interactions between their constituent protons and neutrons are described by the theory of quantum chromodynamics. Previously, scientists focused on individual nucleons in the nucleus and modeled their behavior at high energies. However, it has recently been discovered that short-lived pairs of nucleons with strong mutual correlation are formed inside nuclei, which have a significant effect on the distribution of particles and the general properties of the nuclei. However, until now there was no description of this effect on the distribution of quarks and gluons in the nucleus.
Physicists from Germany, Israel, the United States and France, led by A. W. Denniston from the Massachusetts Institute of Technology and T. Ježo from the University of Münster, described the influence of correlated pairs of nucleons on the distribution of partons in nuclei. To do this, the scientists conducted a detailed analysis of nucleon interactions based on data on deep inelastic lepton scattering, the production of W and Z bosons, and the Drell-Yan effect. The researchers introduced into the calculations not only individual nucleons, as in the classical approach, but also pair correlations, which made it possible to construct a model image of the structure of quarks and gluons in pairs of nucleons.
As a result, scientists were able to identify for the first time universal parameters for quarks and gluons in pairs of correlated nucleons, confirming the unique properties of such bonds in nuclei. It turned out that pairs of nucleons significantly affect the distribution of elementary particles, especially at high energy levels. According to the authors, their results also confirm the hypothesis of the dominance of proton-neutron pairs in most nuclei, especially at high energies.
Physicists believe that the results of their research will help in studying the nature of atomic nuclei and the relationship between nuclear and quark structures. We wrote about how physicists study atomic nuclei and improve the theory using the example of studying the charge radius of nickel isotopes.