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Extraction of ground-state nuclear deformations from ultrarelativistic heavy-ion collisions: Nuclear structure physics context

J. Dobaczewski1,2,*, A. Gade3,4,†, K. Godbey3,‡, R. V. F. Janssens5,6,§, and W. Nazarewicz3,4,∥

  • *Contact author: jacek.dobaczewski@york.ac.uk
  • †Contact author: gade@frib.msu.edu
  • ‡Contact author: godbey@frib.msu.edu
  • §Contact author: rvfj@email.unc.edu
  • ∥Contact author: witek@frib.msu.edu
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Phys. Rev. Research 7, 043159 – Published 12 November, 2025

DOI: https://doi.org/10.1103/kngg-1ccb

Abstract

The collective-flow-assisted nuclear shape-imaging method in ultrarelativistic heavy-ion collisions (UHICs) has recently been used to characterize nuclear collective states. In this paper, we assess the foundations of the shape-imaging technique employed in these studies. We argue that some current UHIC nuclear imaging techniques neglect fundamental aspects of spontaneous symmetry breaking and symmetry restoration in colliding ions and incorrectly infer one-body multipole moments from studies of nucleonic correlations. Therefore, the impact of this approach on nuclear structure research has been overstated. Conversely, efforts to incorporate existing knowledge on nuclear shapes into analysis pipelines can be beneficial for benchmarking tools and calibrating models used to extract information from ultrarelativistic heavy-ion experiments.

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Phys. Rev. Research 7, 043159– Published 12 November, 2025
  • Received 14 July 2025
  • Accepted 25 October 2025
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