K. Bloom

Study of the B0 semileptonic decay spectrum at the Y(4S) resonance

We have made a first measurement of the lepton momentum spectrum in a sample of events enriched in neutral Bs through a partial reconstruction of B{sup 0} {yields} D*{sup -}{ell}{sup +}{nu}. This spectrum, measured with 2.38 fb{sup -1} of data collected at the {Upsilon}(4S) resonance by the CLEO II detector, is compared directly to the inclusive lepton spectrum from all {Upsilon}(4S) events in the same data set. These two spectra are consistent with having the same shape above 1.5 GeV/c. From the two spectra and two other CLEO measurements, we obtain the B{sup 0} and B{sup +} semileptonic branching fractions, b{sub 0} and b{sub +}, their ratio, and the production ratio f{sub +-}/f{sub 00} of B{sup +} and B{sup 0} pairs at the {Upsilon}(4S). We report b{sub +}/b{sub 0} = 0.950{sub -0.080}{sup +0.117} {+-} 0.091, b{sub 0} = (10.78 {+-} 0.60 {+-} 0.69)%, and b{sub +} = (10.25 {+-} 0.57 {+-} 0.65)%. b{sub +}/b{sub 0} is equivalent to the ratio of charged to neutral B lifetimes, {tau}{sub +}/{tau}{sub 0}.

Observation of the Decay D s + → ωπ +

Using e{sup +}e{sup {minus}} annihilation data collected by the CLEOII detector at CESR, we have observed the decay D{sup +}{sub s}{r_arrow}{omega}{pi}{sup +} . This final state may be produced through the annihilation decay of the D{sup +}{sub s} , or through final state interactions. We find a branching ratio of {Gamma}(D{sup +}{sub s}{r_arrow}{omega}{pi}{sup +})/{Gamma}(D{sup +}{sub s}{r_arrow} {eta}{pi}{sup +})=0.16{plus_minus}0.04{plus_minus}0 .03 , where the first error is statistical and the second is systematic. {copyright} {ital 1997} {ital The American Physical Society}Using e+e- annihilation data collected by the CLEO~II detector at CESR, we have observed the decay Ds+ to omega pi+. This final state may be produced through the annihilation decay of the Ds+, or through final state interactions. We find a branching ratio of [Gamma(Ds+ to omega pi+)/Gamma(Ds+ to eta pi+)]=0.16+-0.04+-0.03, where the first error is statistical and the second is systematic.