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Published on: February 3, 2014
Elliptic and triangular flow in event-by-event D=3+1 viscous hydrodynamics
Björn Schenke1, Sangyong Jeon, Charles Gale
1Department of Physics, McGill University, Montreal, Quebec, Canada.
Physical Review Letters
|March 17, 2011
Summary
We simulated gold-gold collisions at 200 GeV to study how initial state fluctuations and viscosity affect elliptic flow (v2) and triangular flow (v3). These factors are crucial for understanding particle behavior in these high-energy collisions.
Area of Science:
- Nuclear Physics
- High-Energy Physics
- Quantum Chromodynamics
Background:
- Heavy-ion collisions create a quark-gluon plasma.
- Understanding the properties of this plasma is key to nuclear physics.
- Flow coefficients quantify the collective expansion of the plasma.
Purpose of the Study:
- To investigate the impact of initial state fluctuations and viscosity on elliptic (v2) and triangular (v3) flow coefficients.
- To analyze these coefficients as functions of transverse momentum and pseudorapidity.
- To determine the precision of η/s extraction using simultaneous v2 and v3 measurements.
Main Methods:
- Event-by-event (3+1)D viscous hydrodynamic simulations.
- Analysis of gold-gold (Au+Au) collisions at a center-of-mass energy of 200 GeV per nucleon.
- Study of the centrality dependence of flow coefficients.
Main Results:
- Initial state fluctuations are essential for reproducing the measured centrality dependence of elliptic flow.
- Viscous effects and initial fluctuations influence both v2 and v3 coefficients.
- The interplay between v2 and v3 provides a more precise determination of the viscosity to entropy density ratio (η/s).
Conclusions:
- Hydrodynamic simulations with initial state fluctuations accurately describe experimental data.
- Simultaneous measurements of v2 and v3 offer a robust method for constraining the shear viscosity to entropy density ratio (η/s).
- This research advances the understanding of the strongly coupled quark-gluon plasma.
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