6533b7d2fe1ef96bd125ec60
RESEARCH PRODUCT
Pinning down QCD-matter shear viscosity in A + A collisions via EbyE fluctuations using pQCD + saturation + hydrodynamics
Risto PaatelainenKimmo TuominenKari J. EskolaKari J. EskolaHarri Niemisubject
Nuclear and High Energy PhysicsParticle physicsNuclear TheoryHadronFOS: Physical sciences01 natural sciencesNuclear Theory (nucl-th)Nuclear physicsHigh Energy Physics - Phenomenology (hep-ph)initial energy densities0103 physical sciencesNuclear Experiment010306 general physicsNuclear theoryQCD matterPhysicsLarge Hadron Colliderta114010308 nuclear & particles physicsShear viscosityHigh Energy Physics::PhenomenologyPerturbative QCDObservableheavy-ion collisionsHigh Energy Physics - PhenomenologyHigh Energy Physics::ExperimentQCD matterdescription
We compute the initial energy densities produced in ultrarelativistic heavy-ion collisions from NLO perturbative QCD using a saturation conjecture to control soft particle production, and describe the subsequent space-time evolution of the system with hydrodynamics, event by event. The resulting centrality dependence of the low-$p_T$ observables from this pQCD + saturation + hydro ("EKRT") framework are then compared simultaneously to the LHC and RHIC measurements. With such an analysis we can test the initial state calculation, and constrain the temperature dependence of the shear viscosity-to-entropy ratio $\eta/s$ of QCD matter. Using these constraints from the current RHIC and LHC measurements we then predict the charged hadron multiplicities and flow coefficients for the 5.023 TeV Pb+Pb collisions.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-12-16 | Nuclear Physics A |