Quarkonium suppression in pPb collisions at 8.16 TeV with CMS

Final-state effects such as interactions with co-moving particles or quark coalescence can influence the hadronization dynamics of heavy quarks in nuclear collisions. To investigate these phenomena, we present new multidifferential measurements of the $Upsilon(nS)/Upsilon(1S)$ production ratios as functions of rapidity, transverse momentum, and charged-particle multiplicity in proton-lead (pPb) collisions at $sqrt{s_{mathrm{NN}}} = 8.16$ TeV with the CMS detector. These measurements explore a higher multiplicity and achieve significantly improved precision compared to previous measurements at 5.02 TeV. By comparing these relative bottomonium production ratios with recently measured $psi(2S)/J/psi$ ratios in the same system, we examine whether final-state effects manifest differently for charm and bottom quarks during the system's evolution. The results will provide new constraints on heavy-quark hadronization models in the nuclear collisions.