Production of light flavor hadrons in small systems measured by PHENIX at RHIC

Abstract

Abstract With the recent observations of collective behavior of produced particles in small collision systems, measurements of the modification of hadron production in small systems have become increasingly relevant. To study the properties of possible quark-gluon plasma and cold nuclear matter effects PHENIX has performed measurements of light flavor hadrons (π ±, π 0, K *0, φ, and p ¯ ) in a broad set of projectile-target combinations including p+Al, p+Au, d+Au and 3He+Au collisions at s NN = 200 GeV. The obtained invariant transverse momentum spectra and nuclear modification factors are presented and compared to theoretical model predictions where available. The observation of baryon enhancement in the new experimental data and the comparisons with different calculations confirm that quark-gluon plasma could be formed in small collision systems. However, the volume and the lifetime of the medium produced in small collision systems might be insufficient for observation of strangeness enhancement and jet quenching effects.