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Eccentricity Fluctuation in Initial Conditions of Hydrodynamics

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 نشر من قبل Tetsufumi Hirano
 تاريخ النشر 2009
  مجال البحث
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We study effects of eccentricity fluctuations on the elliptic flow coefficient v_2 at mid-rapidity in both Au+Au and Cu+Cu collisions at sqrt{s_{NN}}=200 GeV by using a hybrid model that combines ideal hydrodynamics for space-time evolution of the quark gluon plasma phase and a hadronic transport model for the hadronic matter. We find that the effect of eccentricity fluctuation is modest in semicentral Au+Au collisions but significantly enhances v_2 in Cu+Cu collisions.



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We study effects of eccentricity fluctuations on the elliptic flow coefficient v_2 at mid-rapidity in both Au+Au and Cu+Cu collisions at sqrt{s_NN}=200 GeV by using a hybrid model that combines ideal hydrodynamics for space-time evolution of the quar k gluon plasma phase and a hadronic transport model for the hadronic matter. For initial conditions in hydrodynamic simulations, both the Glauber model and the color glass condensate model are employed to demonstrate the effect of initial eccentricity fluctuations originating from the nucleon position inside a colliding nucleus. The effect of eccentricity fluctuations is modest in semicentral Au+Au collisions, but significantly enhances v_2 in Cu+Cu collisions.
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