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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Viscous hydrodynamic predictions for nuclear collisions at the LHC
Matthew Luzum1, Paul Romatschke
1Department of Physics, University of Washington, Seattle, Washington 98195-1560, USA. mluzum@phys.washington.edu
Physical Review Letters
|April 7, 2010
Summary
Hydrodynamic simulations predict a 10% increase in elliptic flow (v2) for lead-lead collisions at the LHC. Proton-proton collisions show minimal v2, unless the shear viscosity to entropy density ratio (eta/s) is less than 0.08.
Area of Science:
- High-energy nuclear and particle physics.
- Quantum chromodynamics (QCD) matter.
- Heavy-ion collisions.
Background:
- Understanding the properties of the quark-gluon plasma (QGP) is crucial.
- Elliptic flow (v2) serves as a key observable for QGP studies.
- Previous studies at RHIC provided foundational data.
Purpose of the Study:
- To predict the integrated elliptic flow coefficient (v2) for LHC energies.
- To compare v2 in lead-lead (Pb+Pb) and proton-proton (p+p) collisions.
- To investigate the influence of the shear viscosity to entropy density ratio (eta/s) on v2.
Main Methods:
- Utilizing hydrodynamic simulations.
- Modeling Pb+Pb collisions at the Large Hadron Collider (LHC) with square root(s) = 5.5 TeV.
- Modeling p+p collisions at the LHC with square root(s) = 14 TeV.
Main Results:
- A predicted 10% increase in v2 for Pb+Pb collisions at the LHC compared to RHIC energies.
- A prediction of v2 approximately equal to 0 in p+p collisions.
- The condition eta/s < 0.08 is identified as a threshold for non-zero v2 in p+p collisions.
Conclusions:
- Hydrodynamic simulations provide valuable predictions for LHC observables.
- The transition from near-zero v2 in p+p to significant v2 in Pb+Pb highlights the role of initial state geometry and QGP formation.
- The eta/s ratio is a critical parameter influencing the development of collective flow.
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