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[Licence| Download | New Version Template] aeya_v1_0.tar.gz(256662 Kbytes)
Manuscript Title: The iEBE-VISHNU code package for relativistic heavy-ion collisions
Authors: Chun Shen, Zhi Qiu, Huichao Song, Jonah Bernhard, Steffen Bass, Ulrich Heinz
Program title: iEBE-VISHNU
Catalogue identifier: AEYA_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 199(2016)61
Programming language: Fortran, C++, python, bash, SQLite.
Computer: Laptop, desktop, cluster.
Operating system: Tested on GNU/Linux Ubuntu 12.04 x64, Red Hat Linux 6, Mac OS X 10.8+.
RAM: 2G bytes
Keywords: Relativistic viscous hydrodynamics, Quark-gluon plasma, Monte-Carlo simulation.
Classification: 17.11, 17.16, 17.20.

External routines: GNU Scientific Library (GSL), HDF5 (fortran and c++ enabled), Numpy

Nature of problem:
Relativistic heavy-ion collisions are tiny in size (V ~ 10-42m3) and live in a flash (~ 5 x 10-23s). It is impossible to use external probes to study the properties of the quark-gluon plasma (QGP), a novel state of matter created during the collisions. Experiments can only measure the momentum information of stable hadrons, who are the remnants of the collisions. In order to extract the thermal and transport properties of the QGP, one needs to rely on Monte-Carlo event-by-event model simulations, which reverse-engineer the experimental measurements to the early time dynamics of the relativistic heavy-ion collisions.

Solution method:
Relativistic heavy-ion collisions contain multiple stages of evolution. The physics that governs each stage is implemented into individual code components. A general driver script glues all the modular packages as a whole to perform large-scale Monte-Carlo simulations. The final results are stored into SQLite database, which supports standard querying for massive data analysis. By tuning transport coefficients of the QGP as free parameters, e.g. the specific shear viscosity η/s, we can constrain various transport properties of the QGP through model-data comparisons.

Running time:
The following running time is tested on a laptop computer with a 2.4 GHz Intel Core i5 CPU, 4GB memory. All the C++ and Fortran codes are compiled with the GNU Compiler Collection (GCC) 4.9.2 and -O3 optimization.

- p+p 0-5% p+Pb 0-5% Pb+Pb
initial condition generator superMC (100 events, 400x400 grid) 20s 20s 50s
(2+1)-d hydrodynamics VISHNew (1 event, 400x400 grid) 120s 200s 690s
Cooper-Frye freeze-out iSS (500 events, |y| < 4) 4s 15s 350s
hadron cascade UrQMD (1 event, |y| < 4) 0.03s 0.18s 150s

Table 1: Summary of typical running time (in seconds) of individual components in the package. Different types of collisions are simulated at √sNN = 5.02 TeV.