Measurements of ψ(2S) and X(3872) → J/ψπ + π − production in pp collisions at √s=8 TeV with the ATLAS detector


Aaboud M., Aad G., Abbott B., Abdallah J., Abdinov O., Abeloos B., ...Daha Fazla

Journal of High Energy Physics, cilt.2017, sa.1, 2017 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2017 Sayı: 1
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1007/jhep01(2017)117
  • Dergi Adı: Journal of High Energy Physics
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: B physics, Hadron-Hadron scattering (experiments)
  • Ankara Üniversitesi Adresli: Evet

Özet

Differential cross sections are presented for the prompt and non-prompt production of the hidden-charm states X(3872) and ψ(2S), in the decay mode J/ψπ+π−, measured using 11.4 fb−1 of pp collisions at s=8 TeV by the ATLAS detector at the LHC. The ratio of cross-sections X(3872)/ψ(2S) is also given, separately for prompt and non-prompt components, as well as the non-prompt fractions of X(3872) and ψ(2S). Assuming independent single effective lifetimes for non-prompt X(3872) and ψ(2S) production gives RB=ℬ(B→X(3872)+any)ℬ(X(3872)→J/ψπ+π−)/ℬ(B→ψ(2S)+any)ℬ(ψ(2S)→J/ψπ+π−)=(3.95±0.32(stat)±0.08(sys))×10−2 separating short- and long-lived contributions, assuming that the short-lived component is due to Bc decays, gives RB = (3.57 ± 0.33(stat) ± 0.11(sys)) × 10−2, with the fraction of non-prompt X(3872) produced via Bc decays for pT(X(3872)) > 10 GeV being (25 ± 13(stat) ± 2(sys) ± 5(spin))%. The distributions of the dipion invariant mass in the X(3872) and ψ(2S) decays are also measured and compared to theoretical predictions.[Figure not available: see fulltext.]