Amplitude Analysis of B− → D+ π− π− Decays

The Dalitz plot analysis technique is used to study the resonant substructures of B− → D+ π− π− decays in a data sample corresponding to 3.0 fb^−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. A model-independent analysis of the angular moments demonstrates the presence of resonances with spins 1, 2 and 3 at high D+ π− mass. The data are fitted with an amplitude model composed of a quasi-model-independent function to describe the D+ π− S wave together with virtual contributions from the D∗(2007)0 and B0* states, and components corresponding to the D∗2(2460)0, D∗1(2680)0, D∗3(2760)0 and D∗2(3000)0 resonances. The masses and widths of these resonances are determined together with the branching fractions for their production in B− → D+ π− π− decays. The D+ π− S wave has phase motion consistent with that expected due to the presence of the D∗0(2400)0 state. These results constitute the first observations of the D∗3(2760)0 and D∗2(3000)0 resonances, with significances of 10σ and 6.6σ, respectively.