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