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arXiv · 1203.4104

UrQMD calculations of two-pion HBT correlations in central Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV

Qingfeng Li·Gunnar Graef·Marcus Bleicher
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Abstract

Two-pion Hanbury-Brown-Twiss (HBT) correlations for central Pb-Pb collisions at the Large-Hadron-Collider (LHC) energy of $\sqrt{s_{NN}}=2.76$ TeV are investigated for the first time with the microscopic transport model UrQMD (Ultra-relativistic Quantum Molecular Dynamics). The transverse momentum dependence of the Pratt-Bertsch HBT radii is extracted from a three dimensional Gaussian fit to the correlator in the longitudinal co-moving system (LCMS). Qualitative agreement with the ALICE data is obtained, however $R_{out}$ is overpredicted by nearly 50%. The LHC results are also compared to data from the STAR experiment at RHIC. For both energies we find that the calculated $R_O/R_S$ ratio is always larger than data, indicating that the emission in the model is less explosive than observed in the data.

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Qingfeng Li, Gunnar Graef, Marcus Bleicher. 2012-03-22. UrQMD calculations of two-pion HBT correlations in central Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV. https://doi.org/10.1103/physrevc.85.034908

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