STRONG ANTICORRELATION BETWEEN TEMPERATURE AND FLOW

(postscript version of the picture here)

These plots show the chi-sqare maps of fits of a simple thermodynamic model to Pb+Pb (top row) and S+S (bottom row) data (from NA44), using different flow velocity radial profiles. Any one of these panels shows the strong anticorrelation between the temperature and the maximum flow velocity.
It illustrates that this method is not sufficient to pin down the freezeout temperature. A good chi-square (red valley) can be obtained by picking a higher temperature and a correspondingly lower flow velocity.

Reference: S. Esumi, S. Chapman, H. van Hecke, N. Xu: 'Transverse flow at ultrarelativistic energies', submitted to PRC-rapid comm..

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