Azimuthally Integrated HBT Parameters for Charged Pions in Nucleus-Nucleus Interactions versus Collision Energy

Figure 6

Energy dependence of scaled volume of emission region at freeze-out for secondary charged pions in various nucleus-nucleus collisions at  GeV/. Equation (3) is used for calculation of volume values. Experimental results are shown for the same collision, particle, and Coulomb correction types as well as in Figure 4. Error bars are only statistical (for NA44, total uncertainties). Smooth curves are derived from (3) and the fit results for , . The solid line corresponds to the fits of scaled HBT radii by function (7) and dashed line to the fits by specific case , .