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Updated: Jul 4, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Nonperturbative heavy-quark diffusion in the quark-gluon plasma
H van Hees1, M Mannarelli, V Greco
1Cyclotron Institute and Physics Department, Texas A&M University, College Station, TX 77843-3366, USA.
Physical Review Letters
|June 4, 2008
Summary
Heavy-quark transport properties in the quark-gluon plasma (QGP) were studied using nonperturbative methods. Results show diffusion increases with decreasing temperature, supporting a strongly coupled QGP.
Area of Science:
- Nuclear Physics
- High-Energy Physics
- Quantum Chromodynamics
Background:
- Understanding the behavior of heavy quarks (HQ) in the quark-gluon plasma (QGP) is crucial for probing its properties.
- Previous studies often relied on perturbative QCD, potentially missing nonperturbative effects.
Purpose of the Study:
- To evaluate heavy-quark transport properties in the QGP using a nonperturbative many-body approach.
- To investigate the temperature dependence of heavy-quark diffusion and its implications for QGP properties.
Main Methods:
- Employed a Brueckner many-body scheme with interaction potentials from lattice QCD.
- Calculated in-medium T matrices for elastic heavy-quark scattering.
- Utilized relativistic Langevin simulations for spectra and elliptic flow.
Main Results:
- Attractive meson and diquark channels dominate scattering, supporting resonance states up to ~1.5T(c).
- The drag coefficient increases as temperature decreases, diverging from perturbative QCD predictions.
- Simulations show good agreement with experimental electron decay data.
Conclusions:
- The nonperturbative calculation of heavy-quark diffusion is supported by experimental data.
- The findings suggest the quark-gluon plasma exhibits strong coupling characteristics.
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