Observation of the γ(3S) Meson and Suppression of γ States in Pb-Pb Collisions at √sNN=5.02 TeV
Küçük Resim Yok
Tarih
2024
Yazarlar
Tumasyan, A.
Adam, W.
Andrejkovic, J. W.
Bergauer, T.
Chatterjee, S.
Damanakis, K.
Dragicevic, M.
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Amer Physical Soc
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
The production of gamma(2S) and gamma(3S) mesons in lead-lead (Pb-Pb) and proton-proton (pp) collisions is studied in their dimuon decay channel using the CMS detector at the LHC. The gamma(3S) 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 pp collisions are reported for both the gamma(2S) and gamma(3S) 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 gamma yields in Pb-Pb collisions. This suppression increases from peripheral to central Pb-Pb collisions. Furthermore, the suppression is stronger for gamma(3S) mesons compared to gamma(2S) mesons, extending the pattern of sequential suppression of quarkonium states in nuclear collisions previously seen for the J/psi, psi(2S), gamma(1S), and gamma(2S) mesons.
Açıklama
Anahtar Kelimeler
J/Psi Suppression, Bound-States, Deconfinement, Quarkonium
