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Dynamics and Sizes of the Fireball at Freeze-out

Boris Tomasik·Urs Achim Wiedemann·Ulrich Heinz
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Abstract

Analyzing the m_t-spectrum and two-particle correlations of negative hadrons from 158 AGeV/c Pb+Pb collisions at slightly forward rapidities we find a (thermal) freeze-out temperature of about 100 MeV and transverse flow with approximately 0.55c. The M_t-dependence of the correlation radii prefers a box-like transverse density profile over a Gaussian. From an analysis of the pion phase-space density we find pion chemical potential of approximately 60 MeV at thermal freeze-out.

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Boris Tomasik, Urs Achim Wiedemann, Ulrich Heinz. 1999-07-19. Dynamics and Sizes of the Fireball at Freeze-out. https://doi.org/10.1016/s0375-9474(99)00712-5

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