Applicability of viscous hydrodynamics at RHIC

In an earlier work [P. Huovinen and D. Molnar, Phys. Rev. C 79, 014906 (2009) [arXiv:0808.0953 [nucl-th]]] we established that causal Israel-Stewart viscous hydrodynamics is only accurate in RHIC applications at very low shear viscosities 4πηs/s≲1.5−2. We show here that the region of applicability is significantly reduced if bulk viscosity plays a role in the dynamics.