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Parton collisional effect on the conversion of geometry eccentricities into momentum anisotropies in relativistic heavy-ion collisions

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 نشر من قبل Guo-Liang Ma
 تاريخ النشر 2021
  مجال البحث
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We explore parton collisional effects on the conversion of geometry eccentricities into azimuthal anisotropies in Pb+Pb collisions at $sqrt{s_{NN}}$ = 5.02 TeV using a multi-phase transport model. The initial eccentricity $varepsilon_{n}$ (n = 2,3) and flow harmonics $v_{n}$ (n = 2,3) are investigated as a function of the number of parton collisions ($N_{coll}$) during the source evolution of partonic phase. It is found that partonic collisions leads to generate elliptic flow $v_{2}$ and triangular flow $v_{3}$ in Pb+Pb collisions. On the other hand, partonic collisions also result in an evolution of the eccentricity of geometry. The collisional effect on the flow conversion efficiency is therefore studied. We find that the partons with larger $N_{coll}$ show a lower flow conversion efficiency, which reflect differential behaviors with respect to $N_{coll}$. It provides an additional insight into the dynamics of the space-momentum transformation during the QGP evolution from a transport model point of view.

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