Abstract
A search for the CP-violating strong decays η→π+π− and η'(958)→π+π− has been performed using approximately 2.5×107 events of each of the decays D+→π+π+π− and Ds +→π+π+π−, recorded by the LHCb experiment. The data set corresponds to an integrated luminosity of 3.0 fb−1 of pp collision data recorded during LHC Run 1 and 0.3 fb−1 recorded in Run 2. No evidence is seen for D(s) +→π+η(') with η(')→π+π−, and upper limits at 90% confidence level are set on the branching fractions, B(η→π+π−)<1.6×10−5 and B(η'→π+π−)<1.8×10−5. The limit for the η decay is comparable with the existing one, while that for the η' is a factor of three smaller than the previous limit.
Original language | English |
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Pages (from-to) | 233-240 |
Number of pages | 8 |
Journal | Physics Letters B |
Volume | 764 |
DOIs | |
Publication status | Published - 10 Jan 2017 |
Funding
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); NSFC (China); CNRS/IN2P3 (France); BMBF , DFG and MPG (Germany); INFN (Italy); FOM and NWO (The Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MinES and FASO (Russia); MinECo (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kingdom); 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 (United Kingdom), 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 (United Kingdom).
Funders | Funder number |
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Not added | 1681016 |
Conseil Général de Haute-Savoie | |
EPLANET | |
Herchel Smith Fund | |
Labex ENIGMASS | |
MinES | |
OCEVU | |
Région Auvergne | |
Yandex LLC | |
National Science Foundation | |
Alexander von Humboldt-Stiftung | |
H2020 Marie Skłodowska-Curie Actions | |
CERN | |
Science and Technology Facilities Council | ST/N000250/1, ST/H006737/1, ST/N000331/1, ST/K00140X/1, GRIDPP, LHCb Upgrades, 1707993, ST/J004332/1, ST/M004058/1, 1641747, ST/K003410/1, 1708182, LHCb, ST/L003538/1, ST/K004646/1, ST/N001370/1 |
Leverhulme Trust | |
Royal Society | |
Royal Commission for the Exhibition of 1851 | |
European Commission | |
European Research Council | |
Deutsche Forschungsgemeinschaft | |
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung | 166208 |
Stichting voor Fundamenteel Onderzoek der Materie | |
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 | |
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 | |
Centre National de la Recherche Scientifique | |
Financiadora de Estudos e Projetos | |
Institut national de physique nucléaire et de physique des particules | |
Federal Agency for Scientific Organizations | |
Sociedad Española de Reumatología |