Observation of New Charmless Decays of Bottom Hadrons

Abstract

We search for new charmless decays of neutral b hadrons to pairs of charged hadrons, using 1 fb-1 of data collected by the CDF II detector at the Fermilab Tevatron. We report the first observation of the Bs0→K-π+ decay and measure B(Bs0→K-π+)=(5.0±0.7(stat)±0.8(syst))×10-6. We also report the first observation of charmless b-baryon decays, and measure B(Λb0→pπ-)=(3.5±0.6(stat)±0.9(syst))×10-6 and B(Λb0→pK-)=(5.6±0.8(stat)±1.5(syst))×10-6. No evidence is found for other modes, and we set the limit B(Bs0→π+π-)<1.2×10-6 at 90% C.L.