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arXiv · 2307.12568

Thermal conductivity of evolving quark-gluon plasma in the presence of a time-varying magnetic field

Abstract

The effect of the temperature evolution of QGP on its thermal conductivity and elliptic flow is investigated here in the presence of a time-varying magnetic field. Thermal conductivity plays a vital role in the cooling rate of the medium or its temperature evolution. The magnetic field produced during the early stages of (non-central) heavy-ion collisions decays with time, where electrical conductivity plays a significant role. As the medium expands, the electrical and thermal properties change, reflecting the effect in various observables. In this study, we have calculated the thermal conductivity of the QGP medium, incorporating the effects of temperature and magnetic field evolution. We discovered that conductivity significantly depends on the cooling rate, and its value increases due to temperature evolution. Furthermore, the influence of these evolutions on the elliptic flow coefficient is measured, and elliptic flow decreases due to the evolution. We also extend our study for the case of Gubser flow, where, along with the longitudinal Bjorken expansion, the radially transverse expansion is also present.

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Kamaljeet Singh, Jayanta Dey, Raghunath Sahoo. 2023-07-24. Thermal conductivity of evolving quark-gluon plasma in the presence of a time-varying magnetic field. https://doi.org/10.1103/physrevd.109.014018

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