Geometry and Space-Time Extent of Pion Emission Region at FCC Energies

Figure 4

Energy dependence of scaled for secondary charged pions in various nucleus-nucleus collisions at  GeV/. Experimental results are shown for central collisions (for minimum-bias event in the case of E802 for Al + Si), for pairs of mesons (in the cases of ALICE and STAR for both the Cu + Cu and Au + Au at and 200 GeV, for pairs, E802 for Al + Si and NA44 for , for pairs of mesons) and for standard Coulomb correction (in the cases of ALICE, NA44, NA45, PHOBOS, and STAR for both the Cu + Cu and Au + Au at , and 200 GeV, for correction ). Statistical errors are shown (for NA44, total uncertainties). Smooth curves are derived from fit results for scaled BEC radii [15]. The solid line corresponds to the fits of scaled BEC radii by function (7) and dashed line to the fits by specific case .