Fitted HBT Radii Versus Space-Time Variances in Flow-Dominated Models

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Main Author:	Evan Frodermann
Format:	Artículo científico
Language:	en
Published:	Sociedade Brasileira de Física 2007
Subjects:	Física, Astronomía y Matemáticas Non Flow RHIC Gaussian Femtoscopy
Online Access:	Acceder al recurso
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author	Evan Frodermann
author_facet	Evan Frodermann
contents	Fitted HBT Radii Versus Space-Time Variances in Flow-Dominated Models Evan Frodermann Ulrich Heinz Mike Lisa Física, Astronomía y Matemáticas Non Flow RHIC Gaussian Femtoscopy The inability of otherwise successful dynamical models to reproduce the HBT radii extracted from twoparticlecorrelations measured at the Relativistic Heavy Ion Collider (RHIC) is known as the RHIC HBTPuzzle. Most comparisons between models and experiment exploit the fact that for Gaussian sources the HBTradii agree with certain combinations of the space-time widths of the source which can be directly computedfrom the emission function, without having to evaluate, at significant expense, the two-particle correlation function.We here study the validity of this approach for realistic emission function models some of which exhibitsignificant deviations from simple Gaussian behaviour. By Fourier transforming the emission function we computethe 2-particle correlation function and fit it with a Gaussian to partially mimic the procedure used formeasured correlation functions. We describe a novel algorithm to perform this Gaussian fit analytically. Wefind that for realistic hydrodynamic models the HBT radii extracted from this procedure agree better with thedata than the values previously extracted from the space-time widths of the emission function. Although seriousdiscrepancies between the calculated and measured HBT radii remain, we show that a more apples-to-applescomparison of models with data can play an important role in any eventually successful theoretical descriptionof RHIC HBT data. 2007 artículo científico 0103-9733 https://www.redalyc.org/articulo.oa?id=46437607 en http://www.redalyc.org/revista.oa?id=464 Brazilian Journal of Physics application/pdf Sociedade Brasileira de Física Brazilian Journal of Physics (Brasil) Num.3A Vol.37
format	Artículo científico
id	redalyc_46437607
language	en
publishDate	2007
publisher	Sociedade Brasileira de Física
spellingShingle	Fitted HBT Radii Versus Space-Time Variances in Flow-Dominated Models Evan Frodermann Física, Astronomía y Matemáticas Non Flow RHIC Gaussian Femtoscopy Fitted HBT Radii Versus Space-Time Variances in Flow-Dominated Models Evan Frodermann Ulrich Heinz Mike Lisa Física, Astronomía y Matemáticas Non Flow RHIC Gaussian Femtoscopy The inability of otherwise successful dynamical models to reproduce the HBT radii extracted from twoparticlecorrelations measured at the Relativistic Heavy Ion Collider (RHIC) is known as the RHIC HBTPuzzle. Most comparisons between models and experiment exploit the fact that for Gaussian sources the HBTradii agree with certain combinations of the space-time widths of the source which can be directly computedfrom the emission function, without having to evaluate, at significant expense, the two-particle correlation function.We here study the validity of this approach for realistic emission function models some of which exhibitsignificant deviations from simple Gaussian behaviour. By Fourier transforming the emission function we computethe 2-particle correlation function and fit it with a Gaussian to partially mimic the procedure used formeasured correlation functions. We describe a novel algorithm to perform this Gaussian fit analytically. Wefind that for realistic hydrodynamic models the HBT radii extracted from this procedure agree better with thedata than the values previously extracted from the space-time widths of the emission function. Although seriousdiscrepancies between the calculated and measured HBT radii remain, we show that a more apples-to-applescomparison of models with data can play an important role in any eventually successful theoretical descriptionof RHIC HBT data. 2007 artículo científico 0103-9733 https://www.redalyc.org/articulo.oa?id=46437607 en http://www.redalyc.org/revista.oa?id=464 Brazilian Journal of Physics application/pdf Sociedade Brasileira de Física Brazilian Journal of Physics (Brasil) Num.3A Vol.37
title	Fitted HBT Radii Versus Space-Time Variances in Flow-Dominated Models
topic	Física, Astronomía y Matemáticas Non Flow RHIC Gaussian Femtoscopy
url	https://www.redalyc.org/articulo.oa?id=46437607

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