J/ψ and ψ(2S) measurement in p+p collisions √S = 200 and 500 GeV with the STAR experiment

Abstract

In this paper, results on the J/ψ cross section and polarization measured via the dielectron decay channel at mid-rapidity in p + p collisions at √s = 200 and 500 GeV in the STAR experiment are discussed. Also, first measurements of the J/ψ production as a function of the charged-particle multiplicity density and of ψ(2S) to J/ψ ratio at √s = 500 GeV are reported.