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arXiv · 1009.3334

System-size dependence of the pion freeze-out volume as a potential signature for the phase transition to a Quark Gluon Plasma

Qingfeng Li·Caiwan Shen·Marcus Bleicher
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Abstract

Hanburry-Brown-Twiss (HBT) correlation functions and radii of negatively charged pions from C+C, Si+Si, Cu+Cu, and In+In at lower RHIC/SPS energies are calculated with the UrQMD transport model and the CRAB analyzing program. We find a minimum in the excitation function of the pion freeze-out volume at low transverse momenta and around $E_{lab}\sim 20-30A$GeV which can be related to the transition from hadronic to string matter (which might be interpreted as a pre-cursor of the QGP). The existence of the minimum is explained by the competition of two mechanisms of the particle production, resonance decays and string formation/fragmentation.

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Qingfeng Li, Caiwan Shen, Marcus Bleicher. 2010-09-17. System-size dependence of the pion freeze-out volume as a potential signature for the phase transition to a Quark Gluon Plasma. https://doi.org/10.2478/s11534-012-0093-0

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