@article{5d05f3a3de2f4cf88afaf39b02d55383,
title = "Measurement of the branching ratio Γ(Λb 0→ψ(2S)Λ0)/Γ(Λb 0→J/ψΛ0) with the ATLAS detector",
abstract = "An observation of the Λb 0→ψ(2S)Λ0 decay and a comparison of its branching fraction with that of the Λb 0→J/ψΛ0 decay has been made with the ATLAS detector in proton–proton collisions at s=8 TeV at the LHC using an integrated luminosity of 20.6 fb−1. The J/ψ and ψ(2S) mesons are reconstructed in their decays to a muon pair, while the Λ0→pπ− decay is exploited for the Λ0 baryon reconstruction. The Λb 0 baryons are reconstructed with transverse momentum pT>10 GeV and pseudorapidity |η|<2.1. The measured branching ratio of the Λb 0→ψ(2S)Λ0 and Λb 0→J/ψΛ0 decays is Γ(Λb 0→ψ(2S)Λ0)/Γ(Λb 0→J/ψΛ0)=0.501±0.033(stat)±0.019(syst), lower than the expectation from the covariant quark model.",
author = "\{ATLAS Collaboration\} and G. Aad and B. Abbott and J. Abdallah and O. Abdinov and R. Aben and M. Abolins and AbouZeid, \{O. S.\} and H. Abramowicz and H. Abreu and R. Abreu and Y. Abulaiti and Acharya, \{B. S.\} and L. Adamczyk and Adams, \{D. L.\} and J. Adelman and S. Adomeit and T. Adye and Affolder, \{A. A.\} and T. Agatonovic-Jovin and J. Agricola and Aguilar-Saavedra, \{J. A.\} and Ahlen, \{S. P.\} and F. Ahmadov and G. Aielli and H. Akerstedt and {\AA}kesson, \{T. P.A.\} and Akimov, \{A. V.\} and Alberghi, \{G. L.\} and J. Albert and S. Albrand and \{Alconada Verzini\}, \{M. J.\} and M. Aleksa and Aleksandrov, \{I. N.\} and C. Alexa and G. Alexander and T. Alexopoulos and M. Alhroob and G. Alimonti and L. Alio and J. Alison and Alkire, \{S. P.\} and Allbrooke, \{B. M.M.\} and Allport, \{P. P.\} and A. Aloisio and A. Alonso and F. Alonso and C. Alpigiani and Connell, \{S. H.\} and N. Govender and L. Truong",
note = "Publisher Copyright: {\textcopyright} 2015 CERN for the benefit of the ATLAS Collaboration",
year = "2015",
month = dec,
day = "17",
doi = "10.1016/j.physletb.2015.10.009",
language = "English",
volume = "751",
pages = "63--80",
journal = "Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics",
issn = "0370-2693",
publisher = "Elsevier B.V.",
}