Measurement of elliptic flow of J$/\psi$ in $\sqrt{s_{_{NN}}}=200$ GeV Au$+$Au collisions at forward rapidity

TL;DR

This study measures the azimuthal anisotropy (elliptic flow) of J/ψ particles at forward rapidity in gold-gold collisions at 200 GeV, finding no significant elliptic flow, which suggests limited interaction with the quark-gluon plasma.

Contribution

First measurement of J/ψ elliptic flow at forward rapidity in Au+Au collisions at 200 GeV, providing new insights into quark-gluon plasma interactions.

Findings

J/ψ elliptic flow (v2) is consistent with zero across all centralities and pT ranges.

Results align with midrapidity measurements, indicating no strong elliptic flow at forward rapidity.

No significant azimuthal anisotropy observed for J/ψ in the studied conditions.

Abstract

We report the first measurement of the azimuthal anisotropy of J$/\psi$ at forward rapidity ($1.2<|\eta|<2.2$) in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV at the Relativistic Heavy Ion Collider. The data were collected by the PHENIX experiment in 2014 and 2016 with integrated luminosity of 14.5~nb$^{-1}$. The second Fourier coefficient ($v_2$) of the azimuthal distribution of $J/\psi$ is determined as a function of the transverse momentum ($p_T$) using the event-plane method. The measurements were performed for several selections of collision centrality: 0\%--50\%, 10\%--60\%, and 10\%-40\%. We find that in all cases the values of $v_2(p_T)$, which quantify the elliptic flow of J$/\psi$, are consistent with zero. The results are consistent with measurements at midrapidity, indicating no significant elliptic flow of the J$/\psi$ within the quark-gluon-plasma medium at collision energies of $\sqrt{s_{_{NN}}}=200$ GeV.