TY - JOUR AU - LHCb Collaboration (Aaij, R. et al AU - Garcia Martin, L. M. AU - Henry, L. AU - Jashal, B. K. AU - Martinez-Vidal, F. AU - Oyanguren, A. AU - Remon Alepuz, C. AU - Ruiz Vidal, J. AU - Sanchez Mayordomo, C. PY - 2019 DA - 2019// TI - Observation of an Excited B-c(+) State T2 - Phys. Rev. Lett. JO - Physical Review Letters SP - 232001 - 10pp VL - 122 IS - 23 PB - Amer Physical Soc AB - 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 root s = 7, 8, and 13 TeV, the observation of an excited B-c(+) state in the B-c(+)pi(+)pi(-) invariant-mass spectrum is reported. The observed peak has a mass of 6841.2 +/- 0.6(stat) +/- 0.1(syst) +/- 0.8(B-c(+)) MeV/c(2), where the last uncertainty is due to the limited knowledge of the B-c(+) mass. It is consistent with expectations of the B-c*(2(3)S(1))(+) state reconstructed without the low-energy photon from the B-c*(1(3)S(1))(+) -> B-c(+)gamma decay following B-c*(2(3)S(1))(+) -> B-c*(1(3)S(1))(+)pi(+)pi(-). A second state is seen with a global (local) statistical significance of 2.2 sigma (3.2 sigma) and a mass of 6872.1 +/- 1.3(stat) +/- 0.1(syst) +/- 0.8(B-c(+)) MeV/c(2), and is consistent with the B-c(2(1)S(0))(+) state. These mass measurements are the most precise to date. SN - 0031-9007 UR - https://arxiv.org/abs/1904.00081 UR - https://doi.org/10.1103/PhysRevLett.122.232001 DO - 10.1103/PhysRevLett.122.232001 LA - English N1 - WOS:000471988300003 ID - LHCbCollaborationAaij_etal2019 ER -