Importance of non-flow in mixed-harmonic multi-particle correlations in small collision systems

• DOI: 10.1016/j.physletb.2017.12.035
• Publication Date: 2017-12-18T14:07:18Z
• Authors: Peng Huo; Katarína Gajdošová; Jiangyong Jia; You Zhou
• Keywords: Harmonic; Particle (ecology)

Recently CMS Collaboration measured mixed-harmonic four-particle azimuthal correlations, known as symmetric cumulants SC(n,m), in pp and pPb collisions, interpreted the non-zero SC(n,m) evidence for long-range collectivity these small collision systems. Using PYTHIA HIJING models which do not have genuine collectivity, we show that results, obtained with standard cumulant method, could be dominated by non-flow effects associated jet dijets, especially $pp$ collisions. We are largely suppressed using recently proposed subevent methods requiring correlation between two or more pseudorapidity ranges. argue reanalysis of method experiments is necessary before they can used to provide further evidences a multi-particle constraints on theoretical