The resonant structure of the four pion final state in the decay τ → 3ππντ is analyzed using 4.27 million τ+τ− pairs collected by the CLEO II experiment. We search for second class currents in the decay τ → ωπντ using spin-parity analysis and establish an upper limit on the non-vector current contribution. The mass and width of the ρ resonance are extracted from a fit to the τ → ωπντ spectral function. A partial wave analysis of the resonant structure of the τ → 3ππντ decay is performed; the spectral decomposition of the four pion system is dominated by the ωπ and a1π final states.

A study of charm fragmentation into D∗+ s and D + s in e +e− annihilations at √ s = 10.5 GeV is presented. This study using 4.72±0.05 fb−1 of CLEO II data reports measurements of the cross-sections σ(D∗+ s ) and σ(D + s ) in momentum regions above x = 0.44, where x is the Ds momentum divided by the maximum kinematically allowed Ds momentum. The Ds vector to vector plus pseudoscalar production ratio is measured to be PV (x(D + s ) > 0.44) = 0.44± 0.04.

We have searched for the charmless hadronic decay of B-0 mesons into two neutral pions. Using 9.13 fb(-1) taken at the Y(4S) with the CLEO detector, we obtain an improved upper limit for the branching fraction B(B-0-->pi(0)pi(0)) < 5.7 x 10(-6) at the 90% confidence level.

We have studied two-body charmless decays of the $B$ meson into the final states $\rho^0 \rho^0$, $K^{*0} \rho^0$, $K^{*0} K^{*0}$, $K^{*0} \bar{K^{*0}}$, $K^{*+} \rho^0$, $K^{*+} \bar{K^{*0}}$, and $K^{*+} K^{*-}$ using only decay modes with charged daughter particles. Using 9.7 million $B \bar{B}$ pairs collected with the CLEO detector, we place 90% confidence level upper limits on the branching fractions, $(0.46-7.0)\times 10^{-5}$, depending on final state and polarization.

We present the first measurement of the D*+ width using 9/fb of e+ e- data collected near the Upsilon(4S) resonance by the CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction method that takes advantage of the small vertical size of the CESR beam spot to measure the energy release distribution from the D*+ -> D0 pi+ decay. We find Gamma(D*+) = 96 +- 4 (Statistical) +- 22 (Systematic) keV. We also measure the energy release in the decay and compute Delta m = m(D*+) - m(D0) = 145.412 +- 0.002 (Statistical) +- 0.012 (Systematic) MeV/c^2

We have searched for the charmless hadronic decay of B0 mesons into two neutral pions. Using 9.13fb^-1 taken at the Upsilon(4S) with the CLEO detector, we obtain an improved upper limit for the branching fraction BR(B0-->pi0pi0) < 5.7*10^-6 at the 90% confidence level.

Using 13.7 fb^-1 of data recorded by the CLEO detector at CESR, we investigate the spectrum of charmed baryons which decay into Lambda_c^+ pi^- pi^+ and are more massive than the Lambda_c1 baryons. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda_c^+; the other is narrow with an invariant mass of 596 +- 1 +- 2 MeV above the Lambda_c^+ mass. These results are preliminary.

We have measured the branching fraction and photon energy spectrum for the radiative penguin process b-->s gamma. We find Beta(b-->s gamma) = (3.21+/-0.43+/-0.27(+0.18)(-0.10))x10(-4), where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV, = 2.346+/-0.032+/-0.011 GeV, and -(2) = 0.0226+/-0.0066+/-0.0020 GeV(2), where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) the heavy quark effective theory parameter Lambda = 0.35+/-0.08+/-0.10 GeV.

Using 13.6 fb of continuum two-jet e+e− → cc events collected with the CLEO detector, we have searched for baryon number correlations at the primary quark level. We have measured the likelihood for a Λc charmed baryon to be produced in the hemisphere opposite a Λc − relative to the likelihood for a Λc charmed baryon to be produced opposite an anticharmed meson D; in all cases, the reconstructed hadrons must have momentum greater than 2.3 GeV/c. We find that, given a Λc − (reconstructed in five different decay modes), a Λc is observed in the opposite hemisphere (0.72 ± 0.11)% of the time (not corrected for efficiency). By contrast, given a D in one hemisphere, a Λc is observed in the opposite hemisphere only (0.21± 0.02)% of the time. Normalized to the total number of either Λc − or D “tags”, it is therefore 3.52±0.45±0.42 times more likely to find a Λc opposite a Λc − than a D meson. This enhancement is not observed in the JETSET 7.3 e+e− → cc Monte Carlo simulation. 13.30.-a, 13.60.Rj, 13.65.+i, 14.20.Lq Typeset using REVTEX

The tau decays to six-pion final states have been studied with the CLEO detector at the Cornell Electron Storage Ring. The measured branching fractions are B(tau(-)-->2pi(-)pi(+)3pi(0)nu(tau)) = (2.2+/-0.3+/-0.4)x10(-4) and B(tau(-)-->3pi(-)2pi(+)pi(0)nu(tau)) = (1.7+/-0.2+/-0.2)x10(-4). A search for substructure in these decays shows that they are saturated by intermediate states with eta or omega mesons. We present the first observation of the decay tau(-)-->2pi(-)pi(+)omega(nu)tau and the branching fraction is measured to be (1.2+/-0.2+/-0.1)x10(-4). The measured branching fractions are in good agreement with the isospin expectations but somewhat below the conserved-vector-current predictions.

The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties.

We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.

We analyze 9.7 x 10^6 B\bar{B}$ pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Y(4S) resonance. We measure the rates for B^0 -> J/psi K^{(*)0} and B^+ -> J/psi K^{(*)+} decays and use the world-average B-meson lifetime ratio to extract the relative widths f+-/f00 = Gamma(Y(4S) -> B+B-)/Gamma(Y(4S) -> B0\bar{B0}) = = 1.04 +/- 0.07(stat) +/- 0.04(syst). With the assumption that f+- + f00 = 1, we obtain f00 = 0.49 +/- 0.02(stat) +/- 0.01(syst) and f+- = 0.51 +/- 0.02(stat) +/- 0.01(syst). This production ratio and its uncertainty apply to all exclusive B-meson branching fractions measured at the Y(4S) resonance.