Observation of structures in the J/ψ + ψ(2S) mass spectrum with the ATLAS detector


Aad G., Aakvaag E., Abbott B., Abdelhameed S., Abeling K., Abicht N., ...Daha Fazla

Physical Review D, cilt.113, sa.11, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 113 Sayı: 11
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1103/zhkx-k9zl
  • Dergi Adı: Physical Review D
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, INSPEC, MathSciNet, zbMATH
  • İstanbul Üniversitesi Adresli: Evet

Özet

A search for resonant structures in the J/ψ + ψ(2S) mass spectrum is performed using proton-proton collision data at √s = 13 TeV, corresponding to an integrated luminosity of 140 fb−1, recorded by the ATLAS experiment at the LHC. The decay channels of J/ψ + ψ(2S) → 4μ and J/ψ + ψ(2S) → 4μ + 2π are analyzed. An excess near 6.9 GeV is observed in both channels with a combined significance of 8.9σ. No significant signal is observed near 7.2 GeV, and an upper limit on its yield relative to X(6900) is provided. A simultaneous fit with the di-J/ψ channel is carried out under assumptions regarding the resonance interferences, yielding a ratio of the partial decay widths between the J/ψ + ψ(2S) and di-J/ψ channels of 1.08 ± 0.20þ0.40 −0.17 for the resonance near 6.9 GeV.