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Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV

The flow ansatz states that the single-particle distribution of a given event can be described in terms of the complex flow coefficients Vn . Multi-particle distributions can therefore be expressed as products of these single-particle coefficients; a property commonly referred to as factorization. T...

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Autor principal: Bourjau, Christian
Lenguaje:eng
Publicado: 2018
Materias:
Acceso en línea:https://dx.doi.org/10.1088/1742-6596/1070/1/012027
http://cds.cern.ch/record/2631514
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author Bourjau, Christian
author_facet Bourjau, Christian
author_sort Bourjau, Christian
collection CERN
description The flow ansatz states that the single-particle distribution of a given event can be described in terms of the complex flow coefficients Vn . Multi-particle distributions can therefore be expressed as products of these single-particle coefficients; a property commonly referred to as factorization. The amplitudes and phases of the coefficients fluctuate from event to event, possibly breaking the factorization assumption for event-sample averaged multi-particle distributions. Furthermore, non-flow effects such as di-jets may also break the factorization assumption. The factorization breaking with respect to pseudorapidity η provides insights into the fluctuations of the initial conditions of heavy ion collisions and can simultaneously be used to identify regions of the phase space which exhibit non-flow effects. These proceedings present a method to perform a factorization of the two-particle Fourier coefficients V nΔ(ηa , ηb ) which is largely independent of detector effects. AMPT model calculations of Pb-Pb collisions at TeV are used to identify the smallest |Δη|-gap necessary for the factorization assumption to hold. Furthermore, a possible Δη-dependent decorrelation effect in the simulated data is quantified using the empirical parameter . The decorrelation effect observed in the AMPT calculations is compared to results by the CMS collaboration for Pb-Pb collisions at TeV.
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spelling cern-26315142022-01-28T03:09:18Zdoi:10.1088/1742-6596/1070/1/012027http://cds.cern.ch/record/2631514engBourjau, ChristianFactorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeVnucl-exNuclear Physics - ExperimentThe flow ansatz states that the single-particle distribution of a given event can be described in terms of the complex flow coefficients Vn . Multi-particle distributions can therefore be expressed as products of these single-particle coefficients; a property commonly referred to as factorization. The amplitudes and phases of the coefficients fluctuate from event to event, possibly breaking the factorization assumption for event-sample averaged multi-particle distributions. Furthermore, non-flow effects such as di-jets may also break the factorization assumption. The factorization breaking with respect to pseudorapidity η provides insights into the fluctuations of the initial conditions of heavy ion collisions and can simultaneously be used to identify regions of the phase space which exhibit non-flow effects. These proceedings present a method to perform a factorization of the two-particle Fourier coefficients V nΔ(ηa , ηb ) which is largely independent of detector effects. AMPT model calculations of Pb-Pb collisions at TeV are used to identify the smallest |Δη|-gap necessary for the factorization assumption to hold. Furthermore, a possible Δη-dependent decorrelation effect in the simulated data is quantified using the empirical parameter . The decorrelation effect observed in the AMPT calculations is compared to results by the CMS collaboration for Pb-Pb collisions at TeV.The flow ansatz states that the single-particle distribution of a given event can be described in terms of the complex flow coefficients $V_n$. Multi-particle distributions can therefore be expressed as products of these single-particle coefficients; a property commonly referred to as factorization. The amplitudes and phases of the coefficients fluctuate from event to event, possibly breaking the factorization assumption for event-sample averaged multi-particle distributions. Furthermore, non-flow effects such as di-jets may also break the factorization assumption. The factorization breaking with respect to pseudorapidity $\eta$ provides insights into the fluctuations of the initial conditions of heavy ion collisions and can simultaneously be used to identify regions of the phase space which exhibit non-flow effects. These proceedings present a method to perform a factorization of the two-particle Fourier coefficients $V_{n\Delta}(\eta_a, \eta_b)$ which is largely independent of detector effects. AMPT model calculations of Pb-Pb collisions at $\sqrt{s_{\text{NN}}} = 5.02$ TeV are used to identify the smallest $|\Delta\eta|$-gap necessary for the factorization assumption to hold. Furthermore, a possible $\Delta\eta$-dependent decorrelation effect in the simulated data is quantified using the empirical parameter $F_2^\eta$. The decorrelation effect observed in the AMPT calculations is compared to results by the CMS collaboration for Pb-Pb collisions at $\sqrt{s_{\text{NN}}} = 2.76$ TeV.arXiv:1807.05004oai:cds.cern.ch:26315142018-07-13
spellingShingle nucl-ex
Nuclear Physics - Experiment
Bourjau, Christian
Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title_full Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title_fullStr Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title_full_unstemmed Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title_short Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeV
title_sort factorization of two-particle distributions in ampt simulations of pb-pb collisions at $\mathbf{\sqrt{s_{\text{nn}}}} $ = 5.02 tev
topic nucl-ex
Nuclear Physics - Experiment
url https://dx.doi.org/10.1088/1742-6596/1070/1/012027
http://cds.cern.ch/record/2631514
work_keys_str_mv AT bourjauchristian factorizationoftwoparticledistributionsinamptsimulationsofpbpbcollisionsatmathbfsqrtstextnn502tev