Influence of quark content and collision geometry on proton production in heavy ion collisions

Abstract

Proton production have been preivously measured in PHENIX experiment in Au+Au collisions at . It was obtained that protons yields are enhanced over all mesons yields. This phenomenon was called “baryon puzzle”. This paper presents mesurements of protons in asymmetric Cu+Au collisions at in order to investigate influence of collision geometry. Results in Cu+Au and Au+Au systems were found to be in agreement at similar number of participants, which might indicate that proton production in heavy-ion collision scales with the average size of the nuclear overlap region and do not depends on the details of its shape. ln order to investigate influence of quark content on production of protons consisting of three quarks comparison with φ, π 0 -mesons (quark-antiquark pairs) was provided in Cu+Au collisions at the collision energy of 200 GeV. Such information can improve our understanding of quark-gluon plasma and recombination model.