\upsone differential cross section as a function of \pt, at forward (closed symbols) and backward (open symbols) rapidity, at \sqrts. The \pp reference cross section, obtained through the procedure described in Sec. \ref{sec:analysis} and scaled by $A_{\rm Pb}$, is shown as a band. | ![](https://alice-publications.web.cern.ch/sites/default/files/papers/5655/CS_Y1S_pt-101332.png ) |