Superhorizon fluctuations and acoustic oscillations in relativistic heavy-ion collisions

Mishra, Ananta P.; Mohapatra, R. K.; Saumia, P. S.; Srivastava, Ajit M.

doi:10.1103/physrevc.77.064902

Cited by 95 publications

(153 citation statements)

References 36 publications

Supporting

Mentioning

149

Contrasting

Order By: Relevance

“…This has long been considered a sign of significant collective behavior [5], or "elliptic flow", indicating the existence of a strongly-interacting, low-viscosity fluid [6]. However, only recently has it been realized that all such correlations observed between particles separated by a large relative pseudorapidity could be explained by this collective behavior [7][8][9][10][11][12][13][14][15], at least for the bulk of the system. One significant piece of evidence for this view was the recent observation of the factorization [16][17][18][19] of twoparticle correlations into a product of a function of properties of only one of the particles times a function of the properties of the second.…”

Section: Introductionmentioning

confidence: 99%

Breaking of factorization of two-particle correlations in hydrodynamics

et al. 2013

View full text Add to dashboard Cite

The system formed in ultrarelativistic heavy-ion collisions behaves as a nearly-perfect fluid. This collective behavior is probed experimentally by two-particle azimuthal correlations, which are typically averaged over the properties of one particle in each pair. In this Letter, we argue that much additional information is contained in the detailed structure of the correlation. In particular, the correlation matrix exhibits an approximate factorization in transverse momentum, which is taken as a strong evidence for the hydrodynamic picture, while deviations from the factorized form are taken as a signal of intrinsic, "nonflow" correlations. We show that hydrodynamics in fact predicts factorization breaking as a natural consequence of initial state fluctuations and averaging over events. We derive the general inequality relations that hold if flow dominates, and which are saturated if the matrix factorizes. For transverse momenta up to 5 GeV, these inequalities are satisfied in data, but not saturated. We find factorization breaking in event-by-event ideal hydrodynamic calculations that is at least as large as in data, and argue that this phenomenon opens a new window on the study of initial fluctuations.

show abstract

Section: Introductionmentioning

confidence: 99%

Breaking of factorization of two-particle correlations in hydrodynamics

et al. 2013

View full text Add to dashboard Cite

show abstract

“…However, by studying how much of the initial condition information is retained and survives the dynamical evolution it is possible to obtain valuable insight not only on the characteristics of the initial conditions but also on the interactions that occur in the evolution. These conditions can be applied in many physical systems such as in the study of the evolution of our universe and the anisotropy observed in the CMB [1], or in the study of the nuclear reactions in high energy [2].…”

Section: Introductionmentioning

confidence: 99%

Effects of initial state fluctuations in the final state elliptic flow measurements using the NeXSPheRIO model

et al. 2012

View full text Add to dashboard Cite

We present a systematic study of the effects due to initial condition fluctuations in systems formed by heavy-ion collisions using the hydrodynamical simulation code NeXSPheRIO. The study was based on a sample of events generated simulating Au+Au collisions at center of mass energy of 200 GeV per nucleon pair with impact parameter ranging from most central to peripheral collisions. The capability of the NeXSPheRIO code to control and save the initial condition (IC) as well as the final state particles after the 3D hydrodynamical evolution allows for the investigation of the sensitivity of the experimental observables to the characteristics of the early IC. Comparisons of results from simulated events generated using fluctuating initial conditions and smooth initial condition are presented for the experimental observable elliptic flow parameter (v2) as a function of the transverse momentum, pt, and centrality. We compare v2 values estimated using different methods, and how each method responds to effects of fluctuations in the initial condition. Finally, we quantify the flow fluctuations and compare to the fluctuations of the initial eccentricity of the energy density distribution in the transverse plane.

show abstract

“…Collisions of nuclei at the Relativistic Heavy-Ion Collider (RHIC) and the Large Hadron Collider (LHC) create a fireball hot and dense enough to form a Quark Gluon Plasma (QGP) [1]. Anisotropies in the final momentum space distributions can be traced back to spatial anisotropies in the initial state and are used to understand the nature of the fireball [2,3]. These anisotropies are studied using harmonics of the distribution of the az-imuthal angle φ separation between pairs of particles [4][5][6].…”

mentioning

confidence: 99%