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 B ⁰π ⁺ 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 B ₁(5721) ^0,+ and B ²(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 B ⁰π ⁺ 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.]