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arXiv · 1305.1981

Bulk Viscosity Effects in Event-by-Event Relativistic Hydrodynamics

Jacquelyn Noronha-Hostler·Gabriel S. Denicol·Jorge Noronha·Rone P. G. Andrade·Frederique Grassi
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Abstract

Bulk viscosity effects on the collective flow harmonics in heavy ion collisions are investigated, on an event by event basis, using a newly developed 2+1 Lagrangian hydrodynamic code named v-USPhydro which implements the Smoothed Particle Hydrodynamics (SPH) algorithm for viscous hydrodynamics. A new formula for the bulk viscous corrections present in the distribution function at freeze-out is derived starting from the Boltzmann equation for multi-hadron species. Bulk viscosity is shown to enhance the collective flow Fourier coefficients from $v_2(p_T)$ to $v_5(p_T)$ when $% p_{T}\sim 1-3$ GeV even when the bulk viscosity to entropy density ratio, $% ζ/s$, is significantly smaller than $1/(4π)$.

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Jacquelyn Noronha-Hostler, Gabriel S. Denicol, Jorge Noronha, Rone P. G. Andrade, Frederique Grassi. 2013-05-10. Bulk Viscosity Effects in Event-by-Event Relativistic Hydrodynamics. https://doi.org/10.1103/physrevc.88.044916

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