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arXiv · 0709.4507

Bose-Einstein correlations of pion pairs in central Pb+Pb collisions at CERN SPS energies

NA49 Collaboration
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Abstract

Measurements of Bose-Einstein correlations of pion pairs in central Pb+Pb collisions were performed with the NA49 detector at the CERN SPS for beam energies of 20A, 30A, 40A, 80A, and 158A GeV. Correlation functions were measured in the longitudinally co-moving ``out-side-long'' reference frame as a function of rapidity and transverse momentum in the forward hemisphere of the reaction. Radius and correlation strength parameters were obtained from fits of a Gaussian parametrization. The results show a decrease of the radius parameters with increasing transverse momentum characteristic of strong radial flow in the pion source. No striking dependence on pion-pair rapidity or beam energy is observed. Static and dynamic properties of the pion source are obtained from simultaneous fits with a blast-wave model to radius parameters and midrapidity transverse momentum spectra. Predictions of hydrodynamic and microscopic models of Pb+Pb collisions are discussed.

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NA49 Collaboration. 2007-09-27. Bose-Einstein correlations of pion pairs in central Pb+Pb collisions at CERN SPS energies. https://doi.org/10.1103/physrevc.77.064908

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