Disappearance of partonic collectivity in sNN=3GeV Au+Au collisions at RHIC

Dense Nuclear Matter Equation of State from Heavy-Ion Collisions

“…A comparison of results from the √ s NN = 3.0 GeV data (see Fig. 14) with UrQMD and JAM simulations indicates a relatively hard EOS (characterized by K 0 = 380 MeV) [94]; similarly, a recent Bayesian analysis of the STAR flow data based on a flexible parametrization of the EOS used in the SMASH transport code results in a relatively hard EOS at moderate densities (characterized by K 0 = 300 ± 60 MeV) with a substantial softening at higher densities [58]. However, both UrQMD and SMASH do not currently include momentum-dependent interactions, which are crucial for a correct description of the transverse-momentum-dependence of the elliptic flow [31].…”

“…Recently, new measurements by the STAR collaboration from the fixed target (FXT) program at RHIC have become available, providing an opportunity to expand the set of world data utilized to deduce the baryonic EOS. A Bayesian analysis study [58], in which the speed of sound was independently varied in specified intervals of baryon density (thus providing a more flexible EOS at higher densities), suggests a tension between the E895 [83,[90][91][92] and STAR [93,94] data. Using only the STAR measurements, the study [58] further found that EOSs which simultaneously describe the slope of the directed flow and the elliptic flow, in the considered energy range of E lab = 2.9-9 AGeV ( √ s NN = 3.0-4.5 GeV), are relatively stiff at lower densities and relatively soft at higher densities (see the region with green vertical stripes in the left panel of Fig.…”

“…9). Results from UrQMD (blue bands), JAM (green bands), and SMASH (orange bands) hadronic transport models were obtained using a relatively hard EOS at moderate densities (characterized by K 0 = 300 in SMASH and K 0 = 380 MeV in JAM and UrQMD), with the EOS used in SMASH becoming significantly softer at high densities (see [58,94] for more details).…”

“…Probing the phase diagram at high densities was possible at RHIC in part due to STAR's capability to shift from a standard collider to a fixed-target (FXT) mode, which was used to scan through the lower energies √ s NN = 3-13.7 GeV (E lab = 2.91-99.06 AGeV), thereby establishing a substantial overlap with the previously discussed AGS experiments [362]. Recently, STAR measured collective flow (v 1 , v 2 ) in collisions at √ s NN = 3.0 GeV [94] and √ s NN = 4.5 GeV [93]. A comparison of results from the √ s NN = 3.0 GeV data (see Fig.…”

“…Among the explored observables, numberof-constituent-quark (NCQ) scaling was used as an important evidence of creation of QGP at the highest RHIC energy of √ s NN = 200 GeV (E lab = 21, 300.0 AGeV) [374]. Recent results point to the breaking of the NCQ scaling in Au+Au collisions at √ s NN = 3 GeV (E lab = 2.91 AGeV) [94].…”