Importance of the Bulk Viscosity of QCD in Ultrarelativistic Heavy-Ion Collisions.

  title={Importance of the Bulk Viscosity of QCD in Ultrarelativistic Heavy-Ion Collisions.},
  author={Sung Ju Ryu and Jean-François Paquet and C. P. Shen and Gabriel S. Denicol and Bjoern Schenke and Sangyong Jeon and Charles Gale},
  journal={Physical review letters},
  volume={115 13},
We investigate the consequences of a nonzero bulk viscosity coefficient on the transverse momentum spectra, azimuthal momentum anisotropy, and multiplicity of charged hadrons produced in heavy ion collisions at LHC energies. The agreement between a realistic 3D hybrid simulation and the experimentally measured data considerably improves with the addition of a bulk viscosity coefficient for strongly interacting matter. This paves the way for an eventual quantitative determination of several QCD… 

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