Multiparticle correlations and higher order harmonics in pPb collisions at √s_(NN) = 8.16 TeV

Abstract

The elliptic and higher-order azimuthal anisotropy Fourier harmonics (vn) are obtained for pPb collisions at √s_(NN) = 8.16 TeV over a wide range of event multiplicities based on multiparticle correlations. The data were collected by the CMS experiment during the 2016 LHC run. A sample of peripheral PbPb collisions at √s_(NN) = 5.02 TeV covering a similar range of event multiplicities to the pPb results is also analyzed for comparison. The ratios of different harmonic moments are obtained for both v_2 and v_3 with high precision, which allows a direct comparison to theoretical predictions assuming a hydrodynamic evolution of the created medium with initial-state density fluctuations, particularly probing the non-Gaussian nature of initial-state fluctuations in small collision systems. The presented results provide crucial insights into the origin of collective long-range correlations observed in small collision systems.

Files

Additional details