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The azimuthal anisotropic flow of identified and unidentified charged particles has been systematically studied in Cu+Au collisions at $sqrt{s_{_{NN}}}$ = 200 GeV for harmonics $n=$ 1-4 in the pseudorapidity range $|eta|<1$. The directed flow in Cu+Au collisions is compared with the rapidity-odd and, for the first time, the rapidity-even components of charged particle directed flow in Au+Au collisions at $sqrt{s_{_{NN}}}$ = 200~GeV. The slope of the directed flow pseudorapidity dependence in Cu+Au collisions is found to be similar to that in Au+Au collisions, with the intercept shifted toward positive $eta$ values, i.e., the Cu-going direction. The mean transverse momentum projected onto the spectator plane, $langle p_xrangle$, in Cu+Au collision also exhibits approximately linear dependence on $eta$ with the intercept at about $etaapprox-0.4$, closer to the rapidity of the Cu+Au system center-of-mass. The observed dependencies find natural explanation in a picture of the directed flow originating partly due the tilted source and partly due to the rapidity dependent asymmetry in the initial density distribution. Charge-dependence of the $langle p_xrangle$ was also observed in Cu+Au collisions, indicating an effect of the initial electric field created by charge difference of the spectator protons in two colliding nuclei. The rapidity-even component of directed flow in Au+Au collisions is close to that in Pb+Pb collisions at $sqrt{s_{_{NN}}}$ = 2.76 TeV, indicating a similar magnitude of dipole-like fluctuations in the initial-state density distribution. Higher harmonic flow in Cu+Au collisions exhibits similar trends to those observed in Au+Au and Pb+Pb collisions and is qualitatively reproduced by a viscous hydrodynamic model and a multi-phase transport model. For all harmonics with $nge2$ we observe an approximate scaling of $v_n$ with the number of constituent quarks.
We have studied the dependence of azimuthal anisotropy $v_2$ for inclusive and identified charged hadrons in Au$+$Au and Cu$+$Cu collisions on collision energy, species, and centrality. The values of $v_2$ as a function of transverse momentum $p_T$ a
We report new STAR measurements of mid-rapidity yields for the $Lambda$, $bar{Lambda}$, $K^{0}_{S}$, $Xi^{-}$, $bar{Xi}^{+}$, $Omega^{-}$, $bar{Omega}^{+}$ particles in Cu+Cu collisions at sNN{200}, and mid-rapidity yields for the $Lambda$, $bar{Lamb
The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC) reports measurements of azimuthal dihadron correlations near midrapidity in $d$$+$Au collisions at $sqrt{s_{_{NN}}}$=200 GeV. These measurements complement recent analyses by expe
Due to the large masses, heavy-flavor quarks are dominantly produced in initial hard scattering processes and experience the whole evolution of the medium produced in heavy-ion collisions at RHIC energies. They are also expected to thermalize slower
We present the first measurement of charge-dependent directed flow in Cu+Au collisions at $sqrt{s_{_{NN}}}$ = 200 GeV. The results are presented as a function of the particle transverse momentum and pseudorapidity for different centralities. A finite