time when the isochronous freeze-out criterion is fulfilled. Compared to the HG the BM-EoS leads to a delayed freeze-out time (i.e. a much longer expansion). While in the first few $fm/c$ of the evolution, the system obeying the BM-EoS expands most violently (due to the high pressure gradient in the QGP phase), once the system enters the mixed phase, its expansion is slowed down considerably. This can be observed as the “kink” in Fig. \[press\_t\]. At the higher beam energy, $E_{lab} = 158A$ GeV, this softening of the EoS is even more pronounced. Since the HG-EoS does not contain any phase transition, no softening can be observed, resulting in the shortest expansion time. The chiral CH-EoS lies in between both extreme cases. Although a small kink can be observed, it is not as pronounced as in the BM-EoS. The effect of changes in the EoS on HBT results has been studied before [@Zschiesche:2001dx], but the great advantages of our approach are the full (3+1) dimensions and the same initial conditions and freeze-out for all three cases and all beam energies without adjusting additional parameters.

CRAB analyzing program and the fitting process
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To calculate the two-particle correlator, the CRAB program 