80 research outputs found
Viscous Hydrodynamics and the Quark Gluon Plasma
One of the most striking results from the Relativistic Heavy Ion Collider is
the strong elliptic flow. This review summarizes what is observed and how these
results are combined with reasonable theoretical assumptions to estimate the
shear viscosity of QCD near the phase transition. A data comparison with
viscous hydrodynamics and kinetic theory calculations indicates that the shear
viscosity to entropy ratio is surprisingly small, . The preferred
range is .Comment: Prepared for QGP
Viscous Corrections to Spectra, Elliptic Flow, and HBT Radii
I compute the first viscous correction to the thermal distribution function.
With this correction, I calculate the effect of viscosity on spectra, elliptic
flow, and HBT radii. Indicating the breakdown of hydrodynamics, viscous
corrections become of order one for GeV. Viscous corrections to
HBT radii are particularly large and reduce the outward and longitudinal radii.
This reduction is a direct consequence of the reduction in longitudinal
pressure.Comment: Proceedings for QM200
Parton energy loss and momentum broadening at NLO in high temperature QCD plasmas
We present an overview of a perturbative-kinetic approach to jet propagation,
energy loss, and momentum broadening in a high temperature quark-gluon plasma.
The leading-order kinetic equations describe the interactions between energetic
jet-particles and a non-abelian plasma, consisting of on-shell thermal
excitations and soft gluonic fields. These interactions include 22
scatterings, collinear bremsstrahlung, and drag and momentum diffusion. We show
how the contribution from the soft gluonic fields can be factorized into a set
of Wilson line correlators on the light cone. We review recent
field-theoretical developments, rooted in the causal properties of these
correlators, which simplify the calculation of the appropriate Wilson lines in
thermal field theory. With these simplifications lattice measurements of
transverse momentum broadening have become possible, and the kinetic equations
describing parton transport have been extended to next-to-leading order in the
coupling g.Comment: Review to appear in QGP5, 40 pages, 12 figure
- …