Experimental Evidence for an Attractive p-φ Interaction

S Acharya, Jonatan Adolfsson, Sumit Basu, Peter Christiansen, Oliver Matonoha, Adrian Nassirpour, Alice Ohlson, Anders Oskarsson, Tuva Richert, Omar Vazquez Rueda, David Silvermyr, N Zurlo, ALICE Collaboration

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This Letter presents the first experimental evidence of the attractive strong interaction between a proton and a φ meson. The result is obtained from two-particle correlations of combined p-φ p¯-φ pairs measured in high-multiplicity pp collisions at s=13 TeV by the ALICE Collaboration. The spin-averaged scattering length and effective range of the p-φ interaction are extracted from the fully corrected correlation function employing the Lednický-Lyuboshits approach. In particular, the imaginary part of the scattering length vanishes within uncertainties, indicating that inelastic processes do not play a prominent role for the p-φ interaction. These data demonstrate that the interaction is dominated by elastic p-φ scattering. Furthermore, an analysis employing phenomenological Gaussian- and Yukawa-type potentials is conducted. Under the assumption of the latter, the N-φ coupling constant is found to be gN-φ=0.14±0.03(stat)±0.02(syst). This work provides valuable experimental input to accomplish a self-consistent description of the N-φ interaction, which is particularly relevant for the more fundamental studies on partial restoration of chiral symmetry in nuclear medium. © 2021 CERN.
Original languageEnglish
Article number172301
JournalPhysical Review Letters
Issue number17
Publication statusPublished - 2021

Subject classification (UKÄ)

  • Subatomic Physics

Free keywords

  • Atomic physics
  • Correlation function
  • Effective range
  • Experimental evidence
  • High multiplicity
  • Imaginary parts
  • Inelastic process
  • Scattering length
  • Strong interaction
  • Two-particle correlations
  • Uncertainty
  • Tellurium compounds
  • article
  • chirality
  • correlation function
  • uncertainty


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