Heavy Ion Collisions with Transverse Dynamics from Evolving AdS Geometries

Apr, 2010
60 pages
Published in:
  • JHEP 09 (2010) 102
e-Print:

Citations per year

201020132016201920225102
Abstract: (arXiv)
Currently there exists no known way to construct the Stress-Energy Tensor (Tμν)(T_{\mu \nu}) of the produced medium in heavy ion collisions at strong coupling from purely theoretical grounds. In this paper, some steps are taken in that direction. In particular, the evolution of TμνT_{\mu \nu} at strong coupling and at high energies is being studied for early proper times (τ)(\tau). This is achieved in the context of the AdS/CFT duality by constructing the evolution of the dual geometry in an AdS5_5 background. Improving the earlier works in the literature, the two incident nuclei have an impact parameter bb and a non-trivial transverse profile. The nuclear matter is modeled by two shock waves corresponding to a non-zero five dimensional bulk Stress-Energy Tensor JMNJ_{MN}. An analytic formula for TμνT_{\mu \nu} at small τ\tau is derived and is used in order to calculate the momentum anisotropy and spatial eccentricity of the medium produced in the collision as a function of the ratio τb\frac{\tau}{b}. The result for eccentricity at intermediate τb\frac{\tau}{b} agrees qualitatively with the results obtained in the context of perturbation theory and by using hydrodynamic simulations. Finally, the problem of the negative energy density and its natural connection to the eikonal approximation is discussed.
  • Gauge-gravity correspondence
  • AdS-CFT Correspondence
  • QCD
  • tensor: energy-momentum
  • heavy ion: scattering
  • approximation: eikonal
  • momentum: anisotropy
  • energy: density
  • dimension: 5
  • strong coupling