I. Arsene

Bio: I. Arsene is an academic researcher from University of Bucharest. The author has contributed to research in topics: Quark–gluon plasma & Pseudorapidity. The author has an hindex of 5, co-authored 6 publications receiving 2124 citations.

On the evolution of the nuclear modification factors with rapidity and centrality in d + Au collisions at s(NN)**(1/2) = 200-GeV

Abstract: We report on a study of the transverse momentum dependence of nuclear modification factors ${R}_{d\mathrm{A}\mathrm{u}}$ for charged hadrons produced in $\mathrm{\text{deuteron}}\text{ }\text{ }+\text{ }\text{ }\mathrm{\text{gold}}$ collisions at $\sqrt{{s}_{NN}}=200\text{ }\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$, as a function of collision centrality and of the pseudorapidity ($\ensuremath{\eta}=0$, 1, 2.2, 3.2) of the produced hadrons. We find a significant and systematic decrease of ${R}_{d\mathrm{A}\mathrm{u}}$ with increasing rapidity. The midrapidity enhancement and the forward rapidity suppression are more pronounced in central collisions relative to peripheral collisions. These results are relevant to the study of the possible onset of gluon saturation at energies reached at BNL RHIC.

Centrality dependent particle production at y=0 and y ~ 1 in Au + Au collisions at s(NN)**(1/2) = 200-GeV

Abstract: Particle production of identified charged hadrons, ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}},{K}^{\ifmmode\pm\else\textpm\fi{}},p$, and $\overline{p}$ in Au+Au collisions at $\sqrt{{s}_{\mathit{NN}}}=$ 200 GeV, has been studied as a function of transverse momentum and collision centrality at $y=0$ and $y~1$ by the BRAHMS experiment at Brookhaven National Laboratory's Relativistic Heavy-Ion Collider. Significant collective transverse flow at kinetic freeze-out has been observed in the collisions. The magnitude of the flow rises with the collision centrality. Proton and kaon yields relative to the pion production increase strongly as the transverse momentum increases and also increase with centrality. Particle yields per participant nucleon show a weak dependence on the centrality for all particle species. Hadron production remains relatively constant within one unit around midrapidity in Au+Au collisions at $\sqrt{{s}_{\mathit{NN}}}=$ 200 GeV.

Centrality dependence of charged particle pseudorapidity distributions from d+Au collisions at s(NN)**(1/2) = 200-GeV

Abstract: Charged-particle pseudorapidity densities are presented for the $d+\mathrm{A}\mathrm{u}$ reaction at $\sqrt{{s}_{NN}}=200\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$ with $\ensuremath{-}4.2\ensuremath{\le}\ensuremath{\eta}\ensuremath{\le}4.2$. The results, from the BRAHMS experiment at BNL Relativistic Heavy-Ion Collider, are shown for minimum-bias events and 0%--30%, 30%--60%, and 60%--80% centrality classes. Models incorporating both soft physics and hard, perturbative QCD-based scattering physics agree well with the experimental results. The data do not support predictions based on strong-coupling, semiclassical QCD. In the deuteron-fragmentation region the central 200 GeV data show behavior similar to full-overlap $d+\mathrm{A}\mathrm{u}$ results at $\sqrt{{s}_{NN}}=19.4\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$.

Glauber Modeling in High Energy Nuclear Collisions

Abstract: We review the theoretical background, experimental techniques, and phenomenology of what is known in relativistic heavy ion physics as the Glauber model, which is used to calculate geometric quantities. A brief history of the original Glauber model is presented, with emphasis on its development into the purely classical, geometric picture used for present-day data analyses. Distinctions are made between the optical limit and Monte Carlo approaches, which are often used interchangeably but have some essential differences in particular contexts. The methods used by the four RHIC experiments are compared and contrasted, although the end results are reassuringly similar for the various geometric observables. Finally, several important RHIC measurements are highlighted that rely on geometric quantities, estimated from Glauber calculations, to draw insight from experimental observables. The status and future of Glauber modeling in the next generation of heavy ion physics studies is briefly discussed.

Electron-Ion Collider: The next QCD frontier: Understanding the glue that binds us all

Abstract: This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on “Gluons and quark sea at high energies” at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users’ communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.