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arXiv · 2306.08665

Bayesian parameter estimation with a new three-dimensional initial-conditions model for ultrarelativistic heavy-ion collisions

Derek Soeder·Weiyao Ke·J. -F. Paquet·Steffen A. Bass
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Abstract

We extend the well-studied midrapidity TRENTo initial-conditions model to three dimensions, thus facilitating (3+1)D modeling and analysis of ultrarelativistic heavy-ion collisions at RHIC and LHC energies. TRENTo-3D is a fast, parametric model of the 3D initial-state geometry, capable of providing initial conditions for (3+1)D models of quark--gluon plasma formation and evolution. It builds on TRENTo's success at modeling the initial nuclear participant thicknesses, longitudinally extending the initial deposition to form a central fireball near midrapidity and two fragmentation regions at forward and backward rapidities. We validate the new model through a large-scale Bayesian calibration, utilizing as observables the rapidity distributions of charged hadrons. For computational efficiency the present effort employs a (1+1)D linearized approximation of ideal hydrodynamics as a stand-in for quark--gluon plasma dynamics. This calibration serves as model validation and paves the way for utilizing TRENTo-3D as an initial-conditions model for state-of-the-art simulation incorporating (3+1)D relativistic viscous hydrodynamics.

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Derek Soeder, Weiyao Ke, J. -F. Paquet, Steffen A. Bass. 2023-06-14. Bayesian parameter estimation with a new three-dimensional initial-conditions model for ultrarelativistic heavy-ion collisions. https://arxiv.org/abs/2306.08665

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