EPJ A Topical Collection: Short-Range Correlations and the EMC Effect

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Published on 10 June 2025

Guest Editors: Or Hen, Douglas Higinbotham, Eliezer Piasetzky, Patrizia Rossi, Axel Schmidt

Short-range correlations (SRCs) between nucleons are to be a universal feature of nuclear structure, seen across the nuclear chart. Correlated nucleons in very close proximity are believed to interact much more strongly with each other than with the rest of the nucleus, leading to a separation of scales. In momentum space, correlated pairs of nucleons have very large relative momenta - larger than the typical nuclear Fermi momentum - while also having a small center-of-mass momentum, i.e., the momentum is balanced within the pair. Because nucleons in SRCs experience a high local nuclear density and tend to have high virtuality, they are an exciting laboratory for learning about dense nuclear matter, the isospin structure of the short-distance nucleon-nucleon interaction, and the role of non-nucleonic degrees of freedom in nuclear structure

One particularly interesting avenue of research is the connection between short-range correlations and the EMC Effect, the observation that partonic structure of the nucleon is modified by the nuclear environment. Such modification is surprising because of the wide gulf between MeV-scale nuclear binding and GeV-scale reactions probing partonic structure. The discovery of the EMC Effect is now over 40 years old, and yet a definitive explanation is still being sought. The correlation between the magnitude of the effect and the prevalence of SRCs across nuclei is an alluring connection that is spurring on new experiments seeking to understand if partonic structure modification stems from high density, large virtuality, both, or neither.

The articles in this Topical Collection on Short-Range Correlations and the EMC Effect present some of the latest research expanding our understanding of the roles SRCs play in nuclear and partonic structure. Included are ideas for new observables, new experiments, and new experimental facilities, that will help answer some of the major open questions about SRCs, including their role in the EMC Effect, their isospin structure, the probe- and scale-dependence of scattering observables, and the search for elusive three-nucleon correlations.

The articles included in the Topical Collection are available here and are freely accessible until 6 August 2025. For further information read the Editorial.