0000000000331819

AUTHOR

H. Holopainen

showing 6 related works from this author

Event-by-event distributions of azimuthal asymmetries in ultrarelativistic heavy-ion collisions

2012

Relativistic dissipative fluid dynamics is a common tool to describe the space-time evolution of the strongly interacting matter created in ultrarelativistic heavy-ion collisions. For a proper comparison to experimental data, fluid-dynamical calculations have to be performed on an event-by-event basis. Therefore, fluid dynamics should be able to reproduce, not only the event-averaged momentum anisotropies, $$, but also their distributions. In this paper, we investigate the event-by-event distributions of the initial-state and momentum anisotropies $\epsilon_n$ and $v_n$, and their correlations. We demonstrate that the event-by-event distributions of relative $v_n$ fluctuations are almost eq…

PhysicsNuclear and High Energy PhysicsNuclear Theoryta114FOS: Physical sciencesNuclear Theory (nucl-th)MomentumViscosityQuantum electrodynamicsQuark–gluon plasmaDissipative systemFluid dynamicsBoundary value problemAnisotropyEvent (particle physics)Physical Review C
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Initial state anisotropies in ultrarelativistic heavy-ion collisions from the Monte Carlo Glauber model

2012

In hydrodynamicalmodeling of heavy-ion collisions the initial state spatial anisotropies translate into momentum anisotropies of the final state particle distributions. Thus, understanding the origin of the initial anisotropies and quantifying their uncertainties is important for the extraction of specific QCD matter properties, such as viscosity, from the experimental data. In this work we study the wounded nucleon approach in the Monte Carlo Glauber model framework, focusing especially on the uncertainties which arise from the modeling of the nucleon-nucleon interactions between the colliding nucleon pairs and nucleon-nucleon correlations inside the colliding nuclei. We compare the black …

PhysicsWork (thermodynamics)Particle physicsNuclear TheoryMonte Carlo methodNuclear TheoryFOS: Physical sciencesNuclear Theory (nucl-th)Nuclear physicsMomentumViscosityHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)AnisotropyNucleonNuclear ExperimentGlauberQCD matter
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Influence of temperature-dependent shear viscosity on elliptic flow at backward and forward rapidities in ultrarelativistic heavy-ion collisions

2014

We explore the influence of a temperature-dependent shear viscosity over entropy density ratio $\eta/s$ on the azimuthal anisotropies v_2 and v_4 of hadrons at various rapidities. We find that in Au+Au collisions at full RHIC energy, $\sqrt{s_{NN}}=200$ GeV, the flow anisotropies are dominated by hadronic viscosity at all rapidities, whereas in Pb+Pb collisions at the LHC energy, $\sqrt{s_{NN}}=2760$ GeV, the flow coefficients are affected by the viscosity both in the plasma and hadronic phases at midrapidity, but the further away from midrapidity, the more dominant the hadronic viscosity is. We find that the centrality and rapidity dependence of the elliptic and quadrangular flows can help…

Nuclear and High Energy PhysicsParticle physicsNuclear TheoryHadronFOS: Physical sciences01 natural sciencesNuclear physicsNuclear Theory (nucl-th)Physics::Fluid DynamicsHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesRapiditySensitivity (control systems)Nuclear Experiment (nucl-ex)010306 general physicsNuclear ExperimentNuclear ExperimentPhysicsta114010308 nuclear & particles physicsEquation of state (cosmology)Elliptic flowHigh Energy Physics - PhenomenologyQuark–gluon plasmaHigh Energy Physics::ExperimentRelativistic Heavy Ion ColliderEnergy (signal processing)Physical review C
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Fluid dynamical response to initial state fluctuations

2014

Abstract We investigate a fluid dynamical response to the fluctuations and geometry of the initial state density profiles in ultrarelativistic heavy ion collisions.

PhysicsNuclear reactionNuclear and High Energy Physicsta114Mathematical model010308 nuclear & particles physicsFluid mechanicsState (functional analysis)Mechanics01 natural sciencesClassical mechanicsFlow (mathematics)State density0103 physical sciencesKinetic theory of gasesHeavy ionNuclear Experiment010306 general physicsNuclear Physics A
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Next-to-leading order improved perturbative QCD + saturation + hydrodynamics model for A + A collisions

2014

We calculate initial conditions for the hydrodynamical evolution in ultrarelativistic heavy-ion collisions at the LHC and RHIC in an improved next-to-leading order perturbative QCD + saturation framework. Using viscous relativistic hydrodynamics, we show that we obtain a good simultaneous description of the centrality dependence of charged particle multiplicities, transverse momentum spectra and elliptic flow at the LHC and at RHIC. In particular, we discuss how the temperature dependence of the shear viscosity is constrained by these data.

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderMathematical modelta114010308 nuclear & particles physicsElliptic flowFOS: Physical sciencesPerturbative QCD01 natural sciencesCharged particleViscosityHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesQuantum field theory010306 general physicsNuclear ExperimentNuclear Physics A
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Multiplicities andpTspectra in ultrarelativistic heavy ion collisions from a next-to-leading order improved perturbative QCD+saturation+hydrodynamics…

2013

We bring the EKRT framework, which combines perturbative QCD (pQCD) minijet production with gluon saturation and hydrodynamics, to next-to-leading order (NLO) in pQCD as rigorously as possible. We chart the model uncertainties, and study the viability and predictive power of the model in the light of the RHIC and LHC measurements in central $A+A$ collisions. In particular, we introduce a new set of measurement functions to define the infrared- and collinear-safe minijet transverse energy, ${E}_{T}$, in terms of which we formulate the saturation. We update the framework with the EPS09 NLO nuclear parton distributions (nPDFs), and study the propagation of the nPDF uncertainties into the compu…

PhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHadronOrder (ring theory)Perturbative QCDParton01 natural sciencesGluonNuclear physics0103 physical sciencesHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsRelativistic Heavy Ion ColliderEnergy (signal processing)Physical Review C
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