@article{e0a439182e8a40cab3bb9107c7354e88,
title = "Evidence for the Rare Decay Σ+ →pμ+μ-",
abstract = "A search for the rare decay Σ+→pμ+μ- is performed using pp collision data recorded by the LHCb experiment at center-of-mass energies s=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. An excess of events is observed with respect to the background expectation, with a signal significance of 4.1 standard deviations. No significant structure is observed in the dimuon invariant mass distribution, in contrast with a previous result from the HyperCP experiment. The measured Σ+→pμ+μ- branching fraction is (2.2-1.3+1.8)×10-8, where statistical and systematic uncertainties are included, which is consistent with the standard model prediction.",
author = "{LHCb Collaboration} and R. Aaij and B. Adeva and M. Adinolfi and Z. Ajaltouni and S. Akar and J. Albrecht and F. Alessio and M. Alexander and {Alfonso Albero}, A. and S. Ali and G. Alkhazov and {Alvarez Cartelle}, P. and Alves, {A. A.} and S. Amato and S. Amerio and Y. Amhis and L. An and L. Anderlini and G. Andreassi and M. Andreotti and Andrews, {J. E.} and Appleby, {R. B.} and F. Archilli and P. D{\textquoteright}argent and {Arnau Romeu}, J. and A. Artamonov and M. Artuso and E. Aslanides and M. Atzeni and G. Auriemma and M. Baalouch and I. Babuschkin and S. Bachmann and Back, {J. J.} and A. Badalov and C. Baesso and S. Baker and V. Balagura and W. Baldini and A. Baranov and Barlow, {R. J.} and C. Barschel and S. Barsuk and W. Barter and F. Baryshnikov and V. Batozskaya and V. Battista and A. Bay and {Calvo Gomez}, M. and X. Vilasis-Cardona",
note = "Funding Information: 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 (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 (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 Sk{\l}odowska-Curie Actions and ERC (European Union), ANR, Labex P2IO and OCEVU, and R{\'e}gion Auvergne-Rh{\^o}ne-Alpes (France), RFBR, RSF and Yandex LLC (Russia), GVA, XuntaGal and GENCAT (Spain), Herchel Smith Fund, the Royal Society, the English-Speaking Union and the Leverhulme Trust (United Kingdom). Publisher Copyright: {\textcopyright} 2018 CERN, for the LHCb Collaboration. Published by the American Physical Society under the terms of the »https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP.",
year = "2018",
month = may,
day = "31",
doi = "10.1103/PhysRevLett.120.221803",
language = "English",
volume = "120",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "22",
}