125595029
Measurement of transverse single-spin asymmetries for J/psi production in polarized p + p collisions at s**(1/2) = 200-GeV
119042314
CHARM PRODUCTION AT LARGE RAPIDITIES IN p+p AND d+Au COLLISIONS AT PHENIX AT RHIC
We study charm production through dimuon and single muon measurements at forward and backward rapidities in p+p and d+Au collisions with the PHENIX muon detectors. We also compare open charm to $J/\psi$ yields in the forward and backward rapidities in d+Au collisions and study the origin of the large forward and backward asymmetry in open charm production observed by the PHENIX experiment.
18595526
Enhancement of singly and multiply strangeness in p-Pb and Pb-Pb collisions at 158A GeV/c
The idea that the reduction of the strange quark suppression in string fragmentation leads to the enhancement of strange particle yield in nucleus-nucleus collisions is applied to study the singly and multiply strange particle production in p-Pb and Pb-Pb collisions at 158A GeV/c. In this mechanism the strange quark suppression factor is related to the effective string tension, which increases in turn with the increase of the energy, of the centrality and of the mass of colliding system. The WA97 observation that the strange particle enhancement increases with the increasing of centrality and of strange quark content in multiply strange particles in Pb-Pb collisions with respect to p-Pb collisions was accounted reasonably.
120048813
A criterion for the order of QGP phase transition
Based on the extended Ginzburg-Landau model, it is shown that the dependences of the scaled factorial moments ln Fq on phase space intervals are different for first- and second-order QGP phase transitions. When ln Fq are fitted to polynomials of X ≡ δ13, the relative sign between the fitted coefficients can be used to judge the order of phase transitions.
120209602
Longitudinal Double Spin Asymmetries in Heavy Flavor Production in Polarized p+p Collisions at s = 200 GeV
One of the main goals of the RHIC spin program is to determine the contribution of gluons to the proton spin. At RHIC energies, heavy quark (charm and beauty) production is expected to be dominated by gluon‐gluon interactions, so a measurement of the double longitudinal spin asymmetry ALL in heavy quark production in polarized p+p collisions directly probes the polarized gluon distribution inside the proton. We present the latest results on an ALL measurement for J/Ψ and open charm production measured by the PHENIX detector.
37119712
Heavy Flavor Production at PHENIX at RHIC
A study of heavy flavor production in different collision systems in various kinematic regions presents an opportunity to probe cold nuclear medium and hot dense matter effects. Results from the PHENIX experiment on J/ψ and open charm production in Au+Au and Cu+Cu collisions at sNN =200 GeV are presented. The data show strong J/ψ suppression in central AA collisions, similar to NA50 results, and strong suppression in high pT open charm production. The J/ψ production in Au+Au and d+Au collisions is compared to understand the cold nuclear medium effects. The data show significant cold nuclear effects in charm production in d+Au collisions at forward and backward rapidity ranges.
126348520
Study Parton Energy Loss in High-energy Heavy-ion Collisions
119230540
Quantitative extraction of the jet transport parameter from combined data at RHIC and LHC
Abstract Using theoretical tools developed by the JET Collaboration in which one employs ( 2 + 1 ) D or ( 3 + 1 ) D hydrodynamic models for the bulk medium evolution and jet quenching models, the combined data on suppression of single inclusive hadron spectra at both RHIC and LHC are systematically analyzed with five different approaches to the parton energy loss. The jet transport parameter is extracted from the best fits to the data with values of q ˆ ≈ 1.2 ± 0.3 and 1.9 ± 0.7 GeV 2 / fm in the center of the most central Au + Au collisions at s = 200 GeV and Pb + Pb collisions at s = 2.67 TeV , respectively, at an initial time τ 0 = 0.6 fm / c for a quark jet with an initial energy of 10 GeV/c.
119023635
Dynamics of giant-gravitons in the LLM geometry and the fractional quantum Hall effect
Abstract The LLM's 1 / 2 BPS solutions of IIB supergravity are known to be closely related to the integer quantum Hall droplets with filling factor ν = 1 , and the giant gravitons in the LLM geometry behave like the quasi-holes in those droplets. In this paper we consider how the fractional quantum Hall effect may arise in this context, by studying the dynamics of giant graviton probes in a special LLM geometry, the AdS 5 × S 5 background, that corresponds to a circular droplet. The giant gravitons we study are D3-branes wrapping on a 3-sphere in S 5 . Their low energy world-volume theory, truncated to the 1 / 2 BPS sector, is shown to be described by a Chern–Simons finite-matrix model. We demonstrate that these giant gravitons may condense at right density further into fractional quantum Hall fluid due to the repulsive interaction in the model, giving rise to the new states in IIB string theory. Some features of the novel physics of these new states are discussed.
123718548
PARTON PRODUCTION AND EQUILIBRATION IN A PQCD-INSPIRED MODEL OF HIGH-ENERGY NUCLEAR COLLISIONS
118419281
Hadronic Trigger using electromagnetic calorimeter and particle identification at high-pT with STAR Detector
We derive a new method to improve the statistics of identified particles at high transverse momentum (\pt) using online-triggered events by the Barrel Electro-Magnetic-Calorimeter (BEMC) detector. The BEMC is used to select hadronic interaction and energy deposit from showers created by charged hadrons ($\pi^{\pm},K^{\pm}$ and $p$($\bar{p}$)) in the BEMC. With this trigger, the statistics of the high \pt particles are significantly enhanced by about a factor of 100 with selection efficiency up to 20%. In addition, resonant states ($\rho^0$, $K^{\star}$) and weak-decay V0 (\Ks and \La(\aLa)) can be constructed by selecting the BEMC-trigger hadron as one of its daughters. We also show that the trigger efficiency can be obtained reliably in simulation and data-driven approaches.