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  • Open Access

Universality of scaling entropy in charged hadron multiplicity distributions at the LHC

L. S. Moriggi*

F. S. Navarra†

M. V. T. Machado‡

  • Instituto de Física, Universidade de São Paulo, Rua do Matão, 1371, CEP 05508-090, Cidade Universitária, São Paulo, SP, Brazil

  • *Contact author: lucasmoriggi@unicentro.br
  • †Contact author: navarra@if.usp.br
  • ‡Contact author: magnus@if.ufrgs.br
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Phys. Rev. D 112, 074019 – Published 16 October, 2025

DOI: https://doi.org/10.1103/lynp-yzk5

Abstract

In this work, we investigate the scaling behavior of the entropy associated with the charged hadron multiplicity distribution P(N) in proton-proton collisions at the LHC. We show that the growth of this entropic indicator as a function of the Bjorken-x variable exhibits universal behavior, consistent with observations from deep inelastic scattering. This universality suggests that the entropy scaling is a property of the initial state and reflects the diffusive nature of gluon dynamics at small x. Furthermore, we demonstrate that high-multiplicity events are not accurately described by traditional Koba-Nielsen-Olesen scaling and require a more precise description based on a diffusion scaling framework. This new scaling emerges naturally from the universal growth of partonic entropy and offers deeper insight into the dynamics of particle production in high-energy hadronic collisions.

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Phys. Rev. D 112, 074019– Published 16 October, 2025
  • Received 11 June 2025
  • Accepted 30 September 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. Funded by SCOAP3.

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