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Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma

The momentum distribution of particle production in heavy-ion collisions encodes information about thermalization processes in the early-stage quark-gluon plasma. We use kinetic theory to study the far-from-equilibrium evolution of an expanding plasma with an anisotropic momentum-space distribution....

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Detalles Bibliográficos
Autores principales: Brewer, Jasmine, Ke, Weiyao, Yan, Li, Yin, Yi
Lenguaje:eng
Publicado: 2022
Materias:
Acceso en línea:http://cds.cern.ch/record/2843126
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author Brewer, Jasmine
Ke, Weiyao
Yan, Li
Yin, Yi
author_facet Brewer, Jasmine
Ke, Weiyao
Yan, Li
Yin, Yi
author_sort Brewer, Jasmine
collection CERN
description The momentum distribution of particle production in heavy-ion collisions encodes information about thermalization processes in the early-stage quark-gluon plasma. We use kinetic theory to study the far-from-equilibrium evolution of an expanding plasma with an anisotropic momentum-space distribution. We identify slow and fast degrees of freedom in the far-from-equilibrium plasma from the evolution of moments of this distribution. At late times, the slow modes correspond to hydrodynamic degrees of freedom and are naturally gapped from the fast modes by the inverse of the relaxation time, $\tau_R^{-1}$. At early times, however, there are an infinite number of slow modes with a gap inversely proportional to time, $\tau^{-1}$. From the evolution of the slow modes we generalize the paradigm of the far-from-equilibrium attractor to vector and tensor components of the energy-momentum tensor, and even to higher moments of the distribution function that are not part of the hydrodynamic evolution. We predict that initial-state momentum anisotropy decays slowly in the far-from-equilibrium phase and may persist until the relaxation time.
id cern-2843126
institution Organización Europea para la Investigación Nuclear
language eng
publishDate 2022
record_format invenio
spelling cern-28431262023-08-19T02:42:46Zhttp://cds.cern.ch/record/2843126engBrewer, JasmineKe, WeiyaoYan, LiYin, YiFar-from-equilibrium slow modes and momentum anisotropy in expanding plasmanucl-thNuclear Physics - TheoryThe momentum distribution of particle production in heavy-ion collisions encodes information about thermalization processes in the early-stage quark-gluon plasma. We use kinetic theory to study the far-from-equilibrium evolution of an expanding plasma with an anisotropic momentum-space distribution. We identify slow and fast degrees of freedom in the far-from-equilibrium plasma from the evolution of moments of this distribution. At late times, the slow modes correspond to hydrodynamic degrees of freedom and are naturally gapped from the fast modes by the inverse of the relaxation time, $\tau_R^{-1}$. At early times, however, there are an infinite number of slow modes with a gap inversely proportional to time, $\tau^{-1}$. From the evolution of the slow modes we generalize the paradigm of the far-from-equilibrium attractor to vector and tensor components of the energy-momentum tensor, and even to higher moments of the distribution function that are not part of the hydrodynamic evolution. We predict that initial-state momentum anisotropy decays slowly in the far-from-equilibrium phase and may persist until the relaxation time.arXiv:2212.00820CERN-TH-2022-196LA-UR-22-32315oai:cds.cern.ch:28431262022-12-01
spellingShingle nucl-th
Nuclear Physics - Theory
Brewer, Jasmine
Ke, Weiyao
Yan, Li
Yin, Yi
Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title_full Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title_fullStr Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title_full_unstemmed Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title_short Far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
title_sort far-from-equilibrium slow modes and momentum anisotropy in expanding plasma
topic nucl-th
Nuclear Physics - Theory
url http://cds.cern.ch/record/2843126
work_keys_str_mv AT brewerjasmine farfromequilibriumslowmodesandmomentumanisotropyinexpandingplasma
AT keweiyao farfromequilibriumslowmodesandmomentumanisotropyinexpandingplasma
AT yanli farfromequilibriumslowmodesandmomentumanisotropyinexpandingplasma
AT yinyi farfromequilibriumslowmodesandmomentumanisotropyinexpandingplasma