Study of B[superscript 0][subscript (s)]→K[superscript 0][subscript S]h[superscript +]h[superscript ′−] decays with first observation of B[superscript 0][subscript s]→K[superscript 0][subscript S]K[superscript ±]π[superscript ∓] and B[superscript 0][subscript s] → K[superscript 0][subscript S]π[superscript +]π[superscript -]

Abstract

A search for charmless three-body decays of B[superscript 0] and B[superscript 0][subscript s] mesons with a K[superscript 0][subscript S] meson in the final state is performed using the pp collision data, corresponding to an integrated luminosity of 1.0 fb[superscript −1], collected at a centre-of-mass energy of 7 TeV recorded by the LHCb experiment. Branching fractions of the B[superscript 0][subscript (s)]→K[superscript 0][subscript S]h[superscript +]h[superscript '−] decay modes (h[superscript (′)] = π, K), relative to the well measured B[superscript 0]→K[superscript 0][subscript S]π[superscript +]π[superscript −] decay, are obtained. First observation of the decay modes B[superscript 0][subscript s]→K[superscript 0][superscript S]K[superscript ±]π[superscript ∓] and B[superscript 0][subscript s]→K[superscript 0][subscript S]π[superscript +]π[superscript −] and confirmation of the decay B[superscript 0]→K[superscript 0][subscript S]K[superscript ±]π[superscript ∓] are reported. The following relative branching fraction measurements or limits are obtained B(B[superscript 0]→K[superscript 0][subscript S]K[superscript ±]π[superscript ∓])/B(B[superscript 0]→K[superscript 0][subscript S]π[superscript +]π[superscript −]) = 0.128 ± 0.017 (stat.) ±0.009 (syst.), B(B[superscript 0]→K[superscript 0][subscript S]K[superscript +]K[superscript −])/ B(B[superscript 0]→K[superscript 0][subscript S]π[superscript +]π[superscript −]) = 0.385 ± 0.031 (stat.) ± 0.023 (syst.), B(B[superscript 0][subscript s]→K[superscript 0][subscript S]π[superscript +]π[superscript −])/B(B[superscript 0]→K[superscript 0][subscript S]π[superscript +]π[superscript −]) = 0.29 ± 0.06 (stat.) ± 0.03 (syst.)±0.02 (f[subscript s]/f[subscript d]), B(B[superscript 0][subscript s]→K[superscript 0][subscript S]K[superscript ±]π[superscript ∓])/B(B[superscript 0]→K[superscript 0][subscript S]π[superscript +]π[superscript −]) = 1.48 ± 0.12 (stat.) ± 0.08 (syst.) ±0.12 (f[subscript s]/f[subscript d])B(B[superscript 0][subscript s] → K[superscript 0][subscript S]K[superscript +]K[superscript −])/B(B[superscript 0] → K[superscript 0][subscript S]π[superscript +]π[superscript −]) ∈ [0.004;0.068] at 90%CL.