Elliptic flow of the dilute Fermi gas: From kinetics to hydrodynamics

Abstract

We use the Boltzmann equation in the relaxation time approximation to study the expansion of a dilute Fermi gas at unitarity. We focus, in particular, on the approach to the hydrodynamic limit. Our main finding are: i) In the regime that has been studied experimentally hydrodynamic effects beyond the Navier-Stokes approximation are small, ii) mean field corrections to the Boltzmann equation are not important, iii) experimental data imply that freezeout occurs very late, that means that the relaxation time remains smaller than the expansion time during the entire evolution of the system, iv) the experimental results also imply that the bulk viscosity is significantly smaller than the shear viscosity of the system.

18 pages, 6 figures

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Cited by in corpus (7)

• Strongly Correlated Quantum Fluids: Ultracold Quantum Gases, Quantum Chromodynamic Plasmas, and Holographic Duality
• Fluid Dynamics and Viscosity in Strongly Correlated Fluids
• Dissipative fluid dynamics for the dilute Fermi gas at unitarity: Anisotropic fluid dynamics
• Model-independent determination of the shear viscosity of a trapped unitary Fermi gas: Application to high temperature data
• Lattice Boltzmann simulations of a two-dimensional Fermi gas at unitarity
• Time-of-flight expansion of trapped dipolar Fermi gases: From the collisionless to the hydrodynamic regime
• Quasiclassical molecular dynamics for the dilute Fermi gas at unitarity