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  • Letter
  • Open Access

Density correlations under global and local charge conservation

Volodymyr Vovchenko

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Phys. Rev. C 110, L061902 – Published 11 December, 2024

DOI: https://doi.org/10.1103/PhysRevC.110.L061902

Abstract

This work presents a formalism to compute spatial n-point correlations of a conserved charge density in a large thermal system in the canonical ensemble, with explicit results presented up to fourth order. The resulting correlators contain local and balancing terms expressed through the grand-canonical susceptibilities for any equation of state. The new formalism is used to introduce a Gaussian local baryon number conservation in (spatial) rapidity in heavy-ion collisions at CERN Large Hadron Collider conditions through a modulation of the balancing term. Connection to the conservation volume Vc approach is established, indicating that the latter is appropriate for observables within a limited range around midrapidity. Quantitative analysis of the experimental data of the ALICE Collaboration on net proton cumulants in central Pb-Pb collisions at sNN=5.02 TeV shows significant evidence for local baryon conservation.

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Phys. Rev. C 110, L061902– Published 11 December, 2024
  • Received 11 September 2024
  • Accepted 22 November 2024
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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. Funded by SCOAP3.

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