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 Physics , 2004, Abstract: The addition of the two Forward TPCs to the STAR detector allows one to measure anisotropic flow at forward pseudorapidities. This made possible the first measurement of directed flow at collision energies of sqrt(s_NN) = 200 GeV. PHOBOS' results on elliptic flow at forward rapidities were confirmed, and the sign of v2 was determined to be positive for the first time at RHIC energies. The higher harmonic, v4, is consistent with the recently suggested v2^2 scaling behavior.
 H. Masui Physics , 2005, DOI: 10.1016/j.nuclphysa.2006.06.077 Abstract: We report the measurement of anisotropic flow at RHIC - PHENIX experiment. We present the v_4 results at sqrt(s_NN) = 200 GeV in Au+Au collision. The scaling ratio of v_4/(v_2)^2 is about 1.5 and it is found to be smaller than the prediction from simple coalescence model. The v_2 for high p_T identified particles ($\sim$ 5 GeV/c) measured with Aerogel Cherenkov Counter are presented. We discuss the constituent quark scaling of v_2 for identified particles. We also report the first observation of v_2 for inclusive charged hadrons as well as identified hadrons at sqrt(s_NN) = 200 GeV in Cu+Cu collisions. The system size dependence of v_2 and scaling properties are discussed.
 Physics , 2014, DOI: 10.1103/PhysRevC.89.044907 Abstract: Anisotropic flow coefficients and their fluctuations are investigated for Au+Au collisions at center of mass energy $\sqrt{s_{NN}}$ = 200 GeV by using a multi-phase transport model with string melting scenario. Experimental results of azimuthal anisotropies by means of the two- and four-particle cumulants are generally well reproduced by the model including both parton cascade and hadronic rescatterings. Event-by-event treatments of the harmonic flow coefficients $v_n$ (for n = 2, 3 and 4) are performed, in which event distributions of $v_n$ for different orders are consistent with Gaussian shapes over all centrality bins. Systematic studies on centrality, transverse momentum ($p_{T}$) and pseudo-rapidity ($\eta$) dependencies of anisotropic flows and quantitative estimations of the flow fluctuations are presented. The $p_{T}$ and $\eta$ dependencies of absolute fluctuations for both $v_2$ and $v_3$ follow similar trends as their flow coefficients. Relative fluctuation of triangular flow $v_3$ is slightly centrality-dependent, which is quite different from that of elliptic flow $v_2$. It is observed that parton cascade has a large effect on the flow fluctuations, but hadronic scatterings make little contribution to the flow fluctuations, which indicates flow fluctuations are mainly modified during partonic evolution stage.
 Physics , 2015, Abstract: Dileptons, as an electromagnetic probe, are crucial to study the properties of Quark-Gluon Plasma (QGP) created in heavy ion collisions. We calculated the invariant mass spectra and the anisotropic emission of thermal dielectrons from Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) energy $\sqrt{s_{NN}}=200$~GeV based on EPOS3. This approach provides a realistic (3+1)-dimensional event-by-event viscous hydrodynamic description of the expanding hot and dense matter with a very particular initial condition, and a large set of hadron data and direct photons (besides $v_{2}$ and $v_{3}$ !) can be successfully reproduced. Thermal dilepton emission from both QGP phase and the hadronic gas are considered, with the emission rates based on Lattice QCD and a vector meson model, respectively. We find that the computed invariant mass spectra (thermal contribution + STAR cocktail) can reproduce the measured ones from STAR at different centralities. Different from other model predictions, the obtained elliptic flow of thermal dileptons is larger than the STAR measurement referring to all dileptons. A clear centrality dependence of thermal dilepton occurs not only to elliptic flow $v_{2}$ but also to high orders for centrality in 0-60\%. At a given centrality, $v_{n}$ of thermal dileptons decreases neatly with $n$ for $2 \leq n \leq 5$.
 Physics , 2012, DOI: 10.1103/PhysRevLett.109.202302 Abstract: We calculate flow observables with the NeXSPheRIO ideal hydrodynamic model and make the first comparison to the complete set of mid-rapidity flow measurements made by the PHENIX collaboration in top energy Au+Au collisions. A simultaneous calculation of v_2, v_3, v_4, and the first event-by-event calculation of quadrangular flow defined with respect to the v_2 event plane (v_4{Psi_2}) gives good agreement with measured values, including the dependence on both transverse momentum and centrality. This provides confirmation that the collision system is indeed well described as a quark-gluon plasma with an extremely small viscosity, and that correlations are dominantly generated from collective effects. In addition we present a prediction for v_5.
 STAR Collaboration Physics , 2014, Abstract: We present $\Lambda\Lambda$ correlation measurements in heavy-ion collisions for Au+Au collisions at $\sqrt{s_{NN}}= 200$ GeV using the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). The Lednick\'{y}-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the $\Lambda\Lambda$ correlation function and interaction parameters for di-hyperon searches are discussed.
 Mercedes Lopez Noriega Physics , 2004, Abstract: We present preliminary results from a two-pion intensity interferometry analysis from Au+Au collisions at sqrt{s_{NN}}=200 GeV measured in the STAR detector at RHIC. The dependence of the apparent pion source on multiplicity and transverse momentum are discussed and compared with preliminary results from d+Au and p+p collisions at the same beam energy.
 Physics , 2009, DOI: 10.1016/j.nuclphysa.2009.10.001 Abstract: We report preliminary results of hypertriton observation in heavy-ion collisions at RHIC. We have identified 157 +- 30 candidates in the current sample containing ~10^8 Au+Au events at \sqrt{s_{NN}} = 200 GeV. The production rate of hypertriton is close to that of helium 3. No extra penalty factor is observed for hypertriton, in contrast to results observed at the AGS.
 Sevil Salur Physics , 2004, Abstract: In p+p, d+Au, and Au+Au collisions at \sqrt{s_{NN}}=200 GeV with the STAR detector at RHIC, \Sigma(1385)\to\Lambda+\pi were measured using two techniques; three-particle mixing and a hybrid mixing technique. We present results from both of these methods and compare the invariant mass spectra and the backgrounds.
 Jiangyong Jia Physics , 2007, DOI: 10.1142/S0218301307007362 Abstract: We present the results of the two-particle $\Delta\phi$ correlation between high $p_T$ $\pi^0$ and charged hadrons in Cu+Cu collisions at $\sqrt{s_{NN}} = 200$ GeV. Clear away-side jet signals are seen in central Cu+Cu collisions at all associated hadron $p_T$, albeit suppressed by factor of 2 above 2 GeV/$c$. This level is similar to the suppression seen for inclusive hadrons at high $p_T$ ($>7$ GeV/$c$). However, this agreement is argued to be the result of a cancellation between a flatter away-side parton spectra due to the requirement of high $p_T$ triggers and a bigger energy loss due to a longer path length traversed by the away-side jet.
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