Y. Maravin

First measurement of Γ(D* +) and precision measurement of m D*+-m D0

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

Bounds on the CP Asymmetry in b {r_arrow} s{gamma} Decays

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.

Measurement of exclusive B decays to final states containing a charmed baryon

Using data collected by the CLEO detector in the Upsilon(4S) region, we report new measurements of the exclusive decays of B mesons into final states of the type Lambda_c^+ p-bar n(pi), where n=0,1,2,3. We find signals in modes with one, two and three pions and an upper limit for the two body decay Lambda_c^+ pbar. We also make the first measurements of exclusive decays of B mesons to Sigma_c p-bar n(pi), where n=0,1,2. We find signals in modes with one and two pions and an upper limit for the two body decay Sigma_c p-bar. Measurements of these modes shed light on the mechanisms involved in B decays to baryons.

Search for neutrinoless τ decays involving the KS 0 meson

We have searched for lepton flavor violating decays of the tau lepton with one or two KS0 mesons in the final state. The data used in the search were collected with the CLEO II and II.V detectors at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 13.9 fb^-1 at the Upsilon(4S) resonance. No evidence for signals were found, therefore we have set 90% confidence level (C.L.) upper limits on the branching fractions B(tau -> e KS0) mu KS0) e 2KS0) mu 2KS0) < 3.4e-6. These represent significantly improved upper limits on the two-body decays and first upper limits on the three-body decays.

First observation of B̄ 0→ D* 0π +π +π -π -decays

We report on the observation of B0bar -> D*0 pi+ pi+ pi- pi- decays. The branching ratio is (0.30 +/- 0.07 +/- 0.06)%. Interest in this particular mode was sparked by Ligeti, Luke and Wise who propose it as a way to check the validity of factorization tests in B0bar -> D*+ pi+ pi- pi- pi0 decays.

Kansas Advanced Semiconductor Project

KASP (Kansas Advanced Semiconductor Project) completed the new Layer 0 upgrade for D0, assumed key electronics projects for the US CMS project, finished important new physics measurements with the D0 experiment at Fermilab, made substantial contributions to detector studies for the proposed e+e- international linear collider (ILC), and advanced key initiatives in non-accelerator-based neutrino physics.

Correlated inclusive ΛΛ̄ production in e +e- annihilations at √s∼10.5 GeV

Using a 13.7/fb sample of continuum two-jet e+e- ->qqbar events collected with the CLEO detector, we have searched for correlations between / and /\bar particles, specifically in cases where the opening angle between the two particles is large and each has momentum

First Observation of the Decay B →J/ψϕK

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THE CLEO RICH DETECTOR

1 GeV/c. Such correlations may indicate the presence of baryon number conservation at the primary quark level. A previous CLEO study of /\c/\cbar correlations indicated direct, associated production of primary charmed baryons /\c: e+e- ->ccbar ->/\c/\cbar. That effect was not observed in Monte Carlo simulations. Our current search for similar direct, associated production of / baryons at the primary quark level (e+e- ->ssbar ->/\bar, e.g.) qualitatively indicates a similar effect, although it relies on a Monte Carlo dependent subtraction of background /\bar production (based on the default JETSET 7.4 event generator).

Measurement of the branching ratios for the decays of D(+)(s) to ηπ(+), η′π(+), ηρ(+), and η′ρ(+)

We present the first observation of the decay B->J/psi phi K. Using 9.6 million B meson pairs collected with the CLEO detector, we have observed 10 fully reconstructed B->J/psi phi K candidates, whereas the estimated background is 0.5+/-0.2 events. We obtain a branching fraction of Br(B->J/psi phi K) = (8.8+3.5/-3.0(stat)+/-1.3(syst))*10^-5. This is the first observed