1D K$^{\pm}$K$^{\pm}$ correlation functions (black markers) for four $k_\mathrm{\rm T}$ ranges and for the 0-5% centrality class, fitted with Eq.(3) (red bands). The CFs are normalized to unity in $0.1< q_{\rm inv}< 0.5$ GeV/$c$ statistical uncertainties are shown as bars and systematic boxes. The width of red bands represents the uncertainties of the Eq. (3) fit.