Journal article
Search for the decay D0→π π-μ μ-
R Aaij, B Adeva, M Adinolfi, C Adrover, A Affolder, Z Ajaltouni, J Albrecht, F Alessio, M Alexander, S Ali, G Alkhazov, PA Cartelle, JA Alves, S Amato, S Amerio, Y Amhis, L Anderlini, J Anderson, R Andreassen, JE Andrews Show all
Physics Letters Section B Nuclear Elementary Particle and High Energy Physics | ELSEVIER SCIENCE BV | Published : 2014
Abstract
A search for the D0→π+π-μ+μ- decay, where the muon pair does not originate from a resonance, is performed using proton-proton collision data corresponding to an integrated luminosity of 1.0 fb-1 recorded by the LHCb experiment at a centre-of-mass energy of 7 TeV. No signal is observed and an upper limit on the relative branching fraction with respect to the resonant decay mode D0→π+π-Φ(→μ+μ-) under the assumption of a phase-space model, is found to be B(D0→π+π-μ+μ-)/BD0→π+π-Φ(→μ+μ-)) < 0.96 at 90% confidence level. The upper limit on the absolute branching fraction is evaluated to be B(D0→π+π-μ+μ-) < 5.5 × 10-7 at 90% confidence level. This is the most stringent to date. © 2013 The Authors.
Grants
Awarded by National Science Foundation
Funding Acknowledgements
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 and Region Auvergne (France); BMBF, DFG, HGF and MPG (Germany); SFI (Ireland); INFN (Italy); FOM and NWO (The Netherlands); SCSR (Poland); MEN/IFA (Romania); MinES, Rosatom, RFBR and NRC "Kurchatov Institute" (Russia); MinECo, XuntaGal and GENCAT (Spain); SNSF and SER (Switzerland); NAS Ukraine (Ukraine); STFC (United Kingdom); NSF (USA). We also acknowledge the support received from the ERC under FP7. The Tier1 computing centres are supported by IN2P3 (France), KIT and BMBF (Germany), INFN (Italy), NWO and SURF (The Netherlands), PIC (Spain), GridPP (United Kingdom). We are thankful for the computing resources put at our disposal by Yandex LLC (Russia), as well as to the communities behind the multiple open source software packages that we depend on.