@article{95a7400609e64eb0a348a391babbfd96,
title = "Observation of an Excited Bc+ State",
abstract = "Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date.",
author = "{(LHCb Collaboration)} and R. Aaij and {Abell{\'a}n Beteta}, C. and B. Adeva and M. Adinolfi and Aidala, {C. A.} and Z. Ajaltouni and S. Akar and P. Albicocco and J. Albrecht and F. Alessio and M. Alexander and {Alfonso Albero}, A. and G. Alkhazov and {Alvarez Cartelle}, P. and Alves, {A. A.} and S. Amato and Y. Amhis and L. An and L. Anderlini and G. Andreassi and M. Andreotti and Andrews, {J. E.} and F. Archilli and P. D'Argent and {Arnau Romeu}, J. and A. Artamonov and M. Artuso and K. Arzymatov and E. Aslanides and M. Atzeni and B. Audurier and S. Bachmann and Back, {J. J.} and S. Baker and V. Balagura and W. Baldini and A. Baranov and Barlow, {R. J.} and S. Barsuk and W. Barter and M. Bartolini and F. Baryshnikov and V. Batozskaya and B. Batsukh and A. Battig and S. Blusk and Rudolph, {M. S.} and {Silva Coutinho}, R. and T. Skwarnicki and S. Stone",
note = "Publisher Copyright: {\textcopyright} 2019 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 = "2019",
month = jun,
day = "11",
doi = "10.1103/PhysRevLett.122.232001",
language = "English (US)",
volume = "122",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "23",
}