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arXiv · 1805.04763

Dissociation of heavy quarkonia in an anisotropic hot QCD medium in a Quasi-Particle Model

Abstract

The present article is the follow up work of, Phys.\ Rev.\ D {\bf 94}, 094006 (2016), where we have extended the study of quarkonia dissociation in (momentum) anisotropic hot QCD medium. As evident by the experimentally observed collective flow at RHIC and LHC, the momentum anisotropy is present at almost all the stages after the collision and therefore, it is important to include its effects in the analysis. Employing the in-medium (corrected) potential while considering the anisotropy (both oblate and prolate cases) in the medium, the thermal widths and the binding energies of the heavy quarkonia states (s-wave charmonia and s-wave bottomonia specifically, for radial quantum numbers n = 1 and 2) have been determined. The hot QCD medium effects have been included employing a quasi-particle description. The presence of anisotropy has modified the potential and then the thermal widths and the binding energies of these states in a significant manner. The results show a quite visible shift in the values of dissociation temperatures as compared to the isotropic case. Further, the hot QCD medium interaction effects suppress the dissociation temperature as compared to the case where we consider the medium as a non-interacting ultra-relativistic gas of quarks (anti-quarks) and gluons.

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Mohammad Yousuf Jamal, Indrani Nilima, Vinod Chandra, Vineet Kumar Agotiya. 2018-05-12. Dissociation of heavy quarkonia in an anisotropic hot QCD medium in a Quasi-Particle Model. https://arxiv.org/abs/1805.04763

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