Azimuthal dependence of two-particle transverse momentum current correlations

Summary, in English

Two-particle transverse momentum correlation functions are a powerful technique for understanding the dynamics of relativistic heavy-ion collisions. Among these, the transverse momentum correlator G₂(Δη, Δφ) is of particular interest for its potential sensitivity to the shear viscosity per unit of entropy density η/ s of the quark-gluon plasma formed in heavy-ion collisions. We use the UrQMD, AMPT, and EPOS models for Au–Au at sNN = 200 GeV and Pb–Pb at sNN = 2760 GeV to investigate the long range azimuthal dependence of G₂(Δη, Δφ) , and explore its utility to constrain η/ s based on charged particle correlations. We find that the three models yield quantitatively distinct transverse momentum Fourier harmonics coefficients anpT. We also observe these coefficients exhibit a significant dependence on η/ s in the context of the AMPT model. These observations suggest that exhaustive measurements of the dependence of G₂(Δφ) with collision energy, system size, collision centrality, in particular, offer the potential to distinguish between different theoretical models and their underlying assumptions. Exhaustive analyses of G₂(Δφ) obtained in large and small systems should also be instrumental in establishing new constraints for precise extraction of η/ s.

• Author: Niseem Magdy; Sumit Basu; Victor Gonzalez; Ana Marin; Olga Evdokimov; Roy A. Lacey; Claude Pruneau
• Department/s: Particle and nuclear physics
• Publishing year: 2021-08
• Language: English
• Publication/Series: European Physical Journal C
• Volume: 81
• Issue: 8
• Links: http://dx.doi.org/10.1140/epjc/s10052-021-09568-w
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 1434-6044