119068540
Spherical-Harmonic Expansion Solution of Classical Transport Equations of Quark
The spherical-harmonic method of solving classical transport equation of quark is investigated. The hydrodynamics description of QGP as well as the relation between diffusion approximation and collective flow in nuclear collisions are discussed.
17737818
Non-photonic electron–hadron correlations at STAR
We present STAR's measurements of azimuthal correlations between non-photonic electrons and charged hadrons in p+p, Cu+Cu and Au+Au collisions at GeV. In p+p collisions, from the non-photonic e?h correlation we have extracted the relative B meson semi-leptonic decay contributions to non-photonic electrons up to electron pt ~ 9 GeV/c. In central Cu+Cu and Au+Au collisions where a dense medium is created, we find that the e?h correlation on the away side of the trigger non-photonic electron has been modified in comparison with the expectation from PYTHIA simulations.
14494427
Highlights from STAR: probing the early medium in heavy ion collisions
Abstract We present highlights of recent results from the STAR Collaboration at RHIC, focusing on the properties of the early medium created in heavy ion collisions. We emphasize the strangeness production including the observation of a hypernucleus (the hypertriton), the observation of reaction-plane-dependent angular correlation of charged particles searching for local strong parity violation effects in heavy ion collisions, and the evaluation of the medium viscosity from measurements of elliptic flow. We discuss STAR's plan for the “Critical Point Search” program at RHIC.
119479770
Method for determining event-by-event elliptic flow fluctuations based on the first-order event plane in heavy-ion collisions
A new method is presented for determining event-by-event fluctuations of elliptic flow, v{sub 2}, using first-order event planes. By studying the event-by-event distributions of v{sub 2} observables and first-order event-plane observables, average flow and event-by-event flow fluctuations can be separately determined, making appropriate allowance for the effects of finite multiplicity and nonflow. The method has been tested with Monte Carlo simulations. The connection between flow fluctuations and fluctuations of the initial-state participant eccentricity is discussed.
121637512
Quark Transport Properties in the Region of Coexistence of Both Hadronic and QGP Phases
The physical picture of coexistence of both hadronic and QGP phases is given by Friedberg and T.D. Lee's nontopology soliton model. The transport properties of quark in color space and spin space in a system of two-phase coexistence are investigated from both quantum and classical theories.
119271438
Search for Chiral Magnetic Effects in High-Energy Nuclear Collisions
Abstract We present measurements of pion elliptic flow ( ν 2 ) in Au + Au collisions at s N N = 200 , 62.4 , 39 , 27 and 19.6 GeV , as a function of event-by-event charge asymmetry ( A ± ) , based on data from the STAR experiment at RHIC. We find that π − ( π + ) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins and for all the beam energies under study. The slope parameter ( r ) from ν 2 ( A ± ) difference between π − and π + shows a centrality dependency similar to calculations of the Chiral Magnetic Wave. The measurements of charge separation with respect to the reaction plane in search of Local Parity Violation and the Chiral Magnetic Effect are also presented for Au+Au collisions at s N N = 200 , 62.4 , 39 , 27 , 19.6 , 11.5 and 7.7 GeV , and for U + U collisions at 193 GeV.
121568581
Nonequilibrium Thermodynamics of Dark Energy on Cosmic Apparent Horizon
In recent several years, some works have been done on cosmic thermodynamics. The apparent horizon was regarded as the key characteristic supersurface where thermodynamics can be built on perfectly. However, if the irreversible process is considered, the proper position for building thermodynamics will not be the apparent horizon anymore. The new position is related to dark energy state equation and the irreversible process parameters.