Physical Review Letters, cilt.133, sa.2, 2024 (SCI-Expanded)
The production of Formula Presented and Formula Presented mesons in lead-lead (Pb-Pb) and proton-proton (Formula Presented) collisions is studied in their dimuon decay channel using the CMS detector at the LHC. The Formula Presented meson is observed for the first time in Pb-Pb collisions, with a significance above 5 standard deviations. The ratios of yields measured in Pb-Pb and Formula Presented collisions are reported for both the Formula Presented and Formula Presented mesons, as functions of transverse momentum and Pb-Pb collision centrality. These ratios, when appropriately scaled, are significantly less than unity, indicating a suppression of Formula Presented yields in Pb-Pb collisions. This suppression increases from peripheral to central Pb-Pb collisions. Furthermore, the suppression is stronger for Formula Presented mesons compared to Formula Presented mesons, extending the pattern of sequential suppression of quarkonium states in nuclear collisions previously seen for the Formula Presented, Formula Presented, Formula Presented, and Formula Presented mesons.