Projection of the 3D CF in the ${\rm long}$ direction (black full circles) in three multiplicity classes and two $k_{\rm T}$ ranges fitted (red solid lines) with Eq.~(\ref{eq:BS_3DCF}). Statistical (systematic) uncertainties are shown by bars (boxes). The data are integrated over the range of $|q_i| 0.15$~GeV$/c$ in the non-projected coordinates Vertical lines not belonging to any marker at $|q_{\rm long}|\gtrapprox1.0$~GeV$/c$ are very-large error bars of data points that are out of the chosen $Y$ axis range.