Rapidity dependence of initial state geometry and momentum correlations in p plus Pb collisions

Event geometry and initial state correlations have been invoked as possible explanations of long-range azimuthal correlations observed in high-multiplicity p + p and p + Pb collisions. We study the rapidity ffiffi dependence of initial state momentum correlations and event-by-event geometry inp = 5.02 TeV p + Pb s collisions within the 3 + 1D IP-Glasma model [B. Schenke and S. Schlichting, Phys. Rev. C 94, 044907 (2016)], where the longitudinal structure is governed by Jalilian-Marian-Iancu-McLerran-Weigert-Leonidov-Kovner rapidity evolution of the incoming nuclear gluon distributions. We find that the event geometry is correlated across large rapidity intervals whereas initial state momentum correlations are relatively short-range in rapidity. Based on our results, we discuss implications for the relevance of both effects in explaining the origin of collective phenomena in small systems.

Automated summary

This study investigates the effects of event geometry and initial state correlations on collective phenomena in high-multiplicity collisions in small systems. The research finds that event geometry is correlated across large rapidity intervals, while initial state momentum correlations are relatively short-range in rapidity.