PT Journal AU LHCb Collaboration (Aaij, Rea Martinez-Vidal, F Oyanguren, A Ruiz Valls, P Sanchez Mayordomo, C TI First observation of the rare B+ -> D+K+pi(-) decay SO Physical Review D JI Phys. Rev. D PY 2016 BP 051101 EP 11pp VL 93 IS 5 DI 10.1103/PhysRevD.93.051101 LA English AB The B+ -> D+K+pi(-) decay is observed in a data sample corresponding to 3.0 fb(-1) of pp collision data recorded by the LHCb experiment during 2011 and 2012. The signal significance is 8 sigma and the branching fraction is measured to be B(B+ -> D+K+pi(-)) = (5.31 +/- 0.90 +/- 0.48 +/- 0.35) x 10(-6), where the uncertainties are statistical, systematic and due to the normalization mode B+ -> D-K+pi(+), respectively. The Dalitz plot appears to be dominated by broad structures. Angular distributions are exploited to search for quasi-two-body contributions from B+ -> D*(2)(2460)K-0(+) and B+ -> (D+K*)(892)(0) decays. No significant signals are observed and upper limits are set on their branching fractions. ER