{"arxiv_id":"1406.3333","title":"Bulk viscosity-driven suppression of shear viscosity effects on the flow harmonics at RHIC","abstract":"The interplay between shear and bulk viscosities on the flow harmonics, $v_n$'s, at RHIC is investigated using the newly developed relativistic 2+1 hydrodynamical code v-USPhydro that includes bulk and shear viscosity effects both in the hydrodynamic evolution and also at freeze-out. While shear viscosity is known to attenuate the flow harmonics, we find that the inclusion of bulk viscosity decreases the shear viscosity-induced suppression of the flow harmonics bringing them closer to their values in ideal hydrodynamical calculations. Depending on the value of the bulk viscosity to entropy density ratio, $\\zeta/s$, in the quark-gluon plasma, the bulk viscosity-driven suppression of shear viscosity effects on the flow harmonics may require a re-evaluation of the previous estimates of the shear viscosity to entropy density ratio, $\\eta/s$, of the quark-gluon plasma previously extracted by comparing hydrodynamic calculations to heavy ion data.","primary_cat":"nucl-th","cross_cats":["hep-ph","nucl-ex"],"submitted_at":"2014-06-12T19:41:18+00:00","latest_version":2,"source":"arxiv","source_label":"arXiv","source_url":null,"has_pdf":true,"has_source":false,"verdict":"CONDITIONAL","confidence":"HIGH","one_line_summary":"In event-by-event viscous hydrodynamics, bulk viscosity counteracts the shear-viscosity suppression of elliptic and higher-order flow harmonics at RHIC, bringing them closer to ideal-hydrodynamic values.","novelty_score":5.0,"correctness_risk":"medium","formal_verification":"none","upvotes":0,"downvotes":0,"pith_score":0,"inbound_count":40,"_links":{"html":"https://pith.science/paper/1406.3333","verdict":"/api/v1/verdicts/1406.3333"}}