Study of charmonium production in b -hadron decays and first evidence for the decay Bs0

R. Aaij, B. Adeva, Z. Ajaltouni, S. Akar, F. Alessio, M. Alexander, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves, S. Amato, S. Amerio, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, J. E. Andrews, R. B. Appleby, F. ArchilliP. d’Argent, J. Arnau Romeu, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, M. Baalouch, I. Babuschkin, S. Bachmann, J. J. Back, A. Badalov, C. Baesso, S. Baker, K. Carvalho Akiba, V. Coco, K. De Bruyn, M. Ferro-Luzzi, T. Ketel, J. van Leerdam, M. Merk, C. J.G. Onderwater, G. Raven, M. Schiller, N. Serra, B. Storaci, V. Syropoulos, J. van Tilburg, S. Tolk, P. Tsopelas, N. Tuning, LHCb Collaboration

Research output: Contribution to JournalArticleAcademicpeer-review

Abstract

Using decays to ϕ-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0fb-1, collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting by BC≡B(b→CX)×B(C) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of ϕ mesons, ratios RC2C1≡BC1/BC2 are determined as Rηc(1S)χc0=0.147±0.023±0.011, Rηc(1S)χc1=0.073±0.016±0.006, Rηc(1S)χc2=0.081±0.013±0.005, Rχc0χc1=0.50±0.11±0.01, Rχc0χc2=0.56±0.10±0.01 and Rηc(1S)ηc(2S)=0.040±0.011±0.004. Here and below the first uncertainties are statistical and the second systematic. Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and χ c 2(2 P) states are obtained as Rχc1X(3872)<0.34, Rχc0X(3915)<0.12 and Rχc2χc2(2P)<0.16. Differential cross-sections as a function of transverse momentum are measured for the ηc(1 S) and χc states. The branching fraction of the decay Bs0 is measured for the first time, B(Bs0)=(2.15±0.54±0.28±0.21B)×10-6. Here the third uncertainty is due to the branching fraction of the decay Bs0, which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse ϕ polarization is observed. The measurements allow the determination of the ratio of the branching fractions for the ηc(1 S) decays to ϕϕ and pp¯ as B(ηc(1S))/B(ηc(1S)→pp¯)=1.79±0.14±0.32.

Original languageEnglish
Article number609
JournalEuropean Physical Journal C
Volume77
Issue number9
DOIs
Publication statusPublished - 1 Sept 2017

Funding

Acknowledgements We would like to thank Emi Kou for motivating the studies of charmonium production in LHCb using hadronic final states and the useful discussions regarding charmonium production mechanisms. We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and MPG (Germany); INFN (Italy); NWO (The Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MinES and FASO (Russia); MinECo (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (UK); NSF (USA). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (The Netherlands), PIC (Spain), GridPP (UK), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), PL-GRID (Poland) and OSC (USA). We are indebted to the communities behind the multiple open source software packages on which we depend. Individual groups or members have received support from AvH Foundation (Germany), EPLANET, Marie Skłodowska-Curie Actions and ERC (European Union), Conseil Général de Haute-Savoie, Labex ENIGMASS and OCEVU, Région Auvergne (France), RFBR and Yandex LLC (Russia), GVA, XuntaGal and GENCAT (Spain), Herchel Smith Fund, The Royal Society, Royal Commission for the Exhibition of 1851 and the Leverhulme Trust (UK).

FundersFunder number
Not added1681016
AvH Foundation
CNRS/IN2P3
EPLANET
FASO
Herchel Smith Fund
Labex ENIGMASS
MinES
OCEVU
Région Auvergne
Yandex LLC
National Science Foundation
School of Energy Resources, University of Wyoming
H2020 Marie Skłodowska-Curie Actions
CERN
Science and Technology Facilities CouncilST/L001152/1, ST/N000250/1, ST/H006737/1, ST/N000331/1, GRIDPP, LHCb Upgrades, 1707993, ST/J004332/1, 1641747, ST/M003140/1, ST/K003410/1, 1708182, ST/G005974/1, LHCb
Leverhulme Trust
Royal Society
Royal Commission for the Exhibition of 1851
European Commission
European Research Council
Deutsche Forschungsgemeinschaft
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung166208
National Natural Science Foundation of China
Russian Foundation for Basic Research
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Bundesministerium für Bildung und Forschung
Nederlandse Organisatie voor Wetenschappelijk Onderzoek
Generalitat Valenciana
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Ministry of Science and Technology
Instituto Nazionale di Fisica Nucleare
Narodowe Centrum Nauki
Ministerstwo Nauki i Szkolnictwa Wyższego
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro
National Academy of Sciences of Ukraine
Financiadora de Estudos e Projetos
Conseil Général de l'Aisne

    Fingerprint

    Dive into the research topics of 'Study of charmonium production in b -hadron decays and first evidence for the decay Bs0'. Together they form a unique fingerprint.

    Cite this