First Observation of the Decay B_{s2}^{*}(5840)^{0}→B^{*+}K^{-} and Studies of Excited B_{s}^{0} Mesons

The properties of the orbitally excited (L=1) Bs[superscript 0] states are studied by using 1.0 fb-1 of pp collisions at √s=7 TeV collected with the LHCb detector. The first observation of the B[subscript s2][superscript *](5840)[superscript 0] meson decaying to B[superscript *+]K- is reported, and the corresponding branching fraction measured relative to the B+K- decay mode. The B[subscript s1](5830)[superscript 0]-->B[superscript *+]K- decay is observed as well. The width of the B[subscript s2][superscript *](5840)[superscript 0] state is measured for the first time, and the masses of the two states are determined with the highest precision to date. The observation of the B[subscript s2][superscript *](5840)[superscript 0]-->B[superscript *+]K- decay favors the spin-parity assignment J[superscript P]=2+ for the B[subscript s2][superscript *](5840)[superscript 0] meson. In addition, the most precise measurement of the mass difference m(B[superscript *+])-m(B+)=45.01±0.30(stat)±0.23(syst) MeV/c[superscript 2] is obtained.