Magnetic fields of a large intensity can be generated in peripheral high-energy heavy-ion collisions. Although their intensity drops fast and, moreover, it is not clear whether these fields last long enough to induce a magnetization during the quark-gluon plasma phase, most of the models and simulations predict a significant intensity that lasts up to proper times of order 1 fm after the beginning of the reaction, which is a typical time for the hydrodynamical phase to start. This interval of time is referred to as the pre-equilibrium stage. The evolution of the reaction during pre-equilibrium is thus likely to be influenced by these fields. In this work we adopt a strong field approximation to study the effects of the magnetic field-induced anisotropy on the gluon pressure. We include this anisotropy within the description obtained by means of Effective Kinetic Theory and explore the consequences to reach isotropization at proper times of order 1 fm. We show that when including the magnetic field effects, isotropization is achieved faster.
Azimuthal momentum isotropization in the Quark-Gluon Plasma thermalization
University of Heidelberg（海德堡大学）；Shanghai Institute for Advanced Studies, University of Science and Technology of China（上海高等研究院，中国科学技术大学）；Shanghai Research Center for Quantum Sciences（上海量子科学研究中心）；Hefei National Laboratory（合肥国家实验室）；Universidade de Santiago de Compostela（圣地亚哥德孔波斯特拉大学）；Axencia Galega de Innovación (GAIN), Xunta de Galicia（加利西亚自治区创新署（GAIN））
We explore the out-of-equilibrium dynamics of the Quark-Gluon Plasma at zero and finite net-baryon density based on an effective kinetic theory of Quantum Chromo Dynamics (QCD). By investigating the isotropization of the longitudinal pressure, we determine the relevant time and temperature scales for the onset of viscous hydrodynamics, and quantify the dependence on the chemical composition of the QGP. By extrapolating our results to realistic coupling strength, we discuss phenomenological consequences regarding the role of the pre-equilibrium phase at different collision energies.
(2+2)D Collective Model based on a relativistic Boltzmann equation in the Isotropization Time Approximation: CoMBolt-ITA
TUM School of Natural Sciences, Technische Universität München（慕尼黑工业大学自然科学学院）；School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM)（基础科学研究所粒子与加速器学院）
We use a set of simple angular moments to solve the Boltzmann equation in the relaxation time approximation for a boost invariant longitudinally expanding gluonic plasma. The transition from the free streaming regime at early time to the hydrodynamic regime at late time is well captured by the first two-moments, corresponding to the monopole and quadrupole components of the momentum distribution, or equivalently to the energy density and the difference between the longitudinal and the transverse pressures. We relate this property to the existence of fixed points in the infinite hierarchy of eq…
In this manuscript, it is presented an overview of the Quark-Gluon Plasma properties measured, so far, using hard probes. We will focus on both quantitative and qualitative properties that have been (or are about to be) measured, making a link between the theoretical description and experimental results. Throughout the manuscript, highlights to some of the conferences' results will be given, but without an extensive overview. A personal opinion of the most important developments and critical problems that need more work in the future is presented at the end.
