Precise measurements of the properties of the B₁(5721)^0,+ and B₂^*(5747)^0,+ states and observation of B ^+,0π^−,+ mass structures

Abstract: Invariant mass distributions of B⁺π⁻ and B⁰π⁺ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb⁻¹ of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B₁(5721)^0,+ and B²(5747)^0,+ states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B⁺π⁻ and B⁰π⁺ combinations. The structures are consistent with the presence of four excited B mesons, labelled B_J (5840)^0,+ and B_J (5960)^0,+, whose masses and widths are obtained under different hypotheses for their quantum numbers.[Figure not available: see fulltext.]