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  • Letter
  • Open Access

Femtoscopic signatures of unique nuclear structures in relativistic collisions

Dániel Kincses*

  • *Contact author: kincses@ttk.elte.hu
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Phys. Rev. Research 7, L042028 – Published 31 October, 2025

DOI: https://doi.org/10.1103/1y5m-j966

Abstract

One of the most vital topics of today’s high-energy nuclear physics is the investigation of the nuclear structure of the collided nuclei. Recent studies at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) have shown that several observables, such as the collective flow and transverse-momentum correlations of the produced particles, can be sensitive to various nuclear structure and deformation parameters. Femtoscopy, another essential tool for investigating the space-time geometry of the matter created in nuclear collisions, has not yet been widely applied to such studies. Using a multiphase transport (AMPT) model, in this Letter, it is demonstrated that the femtoscopic source parameters of pion pairs can also serve as a robust signal of unique nuclear structure. Through an analysis of Pb208+Ne20 and Pb208+O16 collisions at sNN=68.5GeV, two collision systems especially relevant to the SMOG2 program of the LHCb experiment, it is shown that a deformed initial shape can significantly affect femtoscopic source parameters. This study highlights the importance of expanding the nuclear structure investigations to femtoscopic observables and serves as a baseline for numerous possible future studies in this new direction.

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Phys. Rev. Research 7, L042028– Published 31 October, 2025
  • Received 6 June 2025
  • Accepted 2 October 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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