First coherent picture of an atomic nucleus made of quarks and gluons

Amazing stuff!

"... "Until now, there have been two parallel descriptions of atomic nuclei, one based on protons and neutrons which we can see at low energies, and another, for high energies, based on quarks and gluons. In our work, we have managed to bring these two so far separated worlds together,"   ...

In their work, physicists ... used data on high-energy collisions, including those collected at the LHC accelerator at CERN laboratory in Geneva. The main objective was to study the partonic structure of atomic nuclei at high energies, currently described by parton distribution functions (PDFs). ...

The novel approach allowed the researchers to determine, for the 18 atomic nuclei studied, parton distribution functions in atomic nuclei, parton distributions in correlated nucleon pairs and even the numbers of such correlated pairs.

The results confirmed the observation known from low-energy experiments that most correlated pairs are proton-neutron pairs ..."

From the abstract:

"We extend the QCD Parton Model analysis using a factorized nuclear structure model incorporating individual nucleons and pairs of correlated nucleons. Our analysis of high-energy data from lepton deep-inelastic scattering, Drell-Yan, and 𝑊 and 𝑍 boson production simultaneously extracts the universal effective distribution of quarks and gluons inside correlated nucleon pairs, and their nucleus-specific fractions. Such successful extraction of these universal distributions marks a significant advance in our understanding of nuclear structure properties connecting nucleon- and parton-level quantities."

First coherent picture of an atomic nucleus made of quarks and gluons

First coherent picture of an atomic nucleus made of quarks and gluons (original news release) "The atomic nucleus is made up of protons and neutrons, particles that exist through the interaction of quarks bonded by gluons. It would seem, therefore, that it should not be difficult to reproduce all the properties of atomic nuclei hitherto observed in nuclear experiments using only quarks and gluons. However, it is only now that physicists, including those from the Institute of Nuclear Physics of the Polish Academy of Sciences in Cracow, have succeeded in doing this."

Modification of Quark-Gluon Distributions in Nuclei by Correlated Nucleon Pairs (open access)

For the first time, quarks and gluons were used to describe properties of atomic nuclei, which until now had been explained by the existence of protons and neutrons. The temporary pair of correlated nucleons is highlighted in purple.