P. U. E. Onyisi

Model-independent determination of the strong-phase difference between D0 and D⊃̄0→KS,L0h+h- (h=π, K) and its impact on the measurement of the CKM angle γ/Φ3

We report the first determination of the relative strong-phase difference between D0→KS,L0K+K- and D 0→KS,L0K+K-. In addition, we present updated measurements of the relative strong-phase difference between D0→KS,L0π+π- and D 0→KS,L0π+π-. Both measurements exploit the quantum coherence between a pair of D0 and D 0 mesons produced from ψ(3770) decays. The strong-phase differences measured are important for determining the Cabibbo-Kobayashi-Maskawa angle γ/ϕ3 in B-→K-D˜0 decays, where D˜0 is a D0 or D 0 meson decaying to KS0h+h- (h=π, K), in a manner independent of the model assumed to describe the D0→KS0h+h- decay. Using our results, the uncertainty in γ/ϕ3 due to the error on the strong-phase difference is expected to be between 1.7° and 3.9° for an analysis using B-→K-D˜0, D˜0→KS0π+π- decays, and between 3.2° and 3.9° for an analysis based on B-→K-D˜0, D˜0→KS0K+K- decays. A measurement is also presented of the CP-odd fraction, F-, of the decay D0→KS0K+K- in the region of the ϕ→K+K- resonance. We find that in a region within 0.01  GeV2/c4 of the nominal ϕ mass squared F->0.91 at the 90% confidence level.

Measurements of D meson decays to two pseudoscalar mesons

Using data collected on the {psi}(3770) resonance and near the D{sub s}*{sup {+-}D}{sub s}{sup {+-}}peak production energy by the CLEO-c detector, we study the decays of the possible D{yields}PP modes and report measurements of or upper limits on all branching fractions for Cabibbo-favored, singly Cabibbo-suppressed, and doubly Cabibbo-suppressed D{yields}PP decays except modes involving K{sub L}{sup 0} (and except D{sup 0{yields}}K{sup +{pi}-}). We normalize with respect to the Cabibbo-favored D modes, D{sup 0{yields}}K{sup -{pi}+}, D{sup +{yields}}K{sup -{pi}+{pi}+}, and D{sub s}{sup +{yields}}K{sup +}K{sub S}{sup 0}.

Measurement of the ηb(1S) mass and the branching fraction for Υ(3S)→γηb(1S)

We report evidence for the ground state of bottomonium, eta_b(1S), in the radiative decay Upsilon(3S) --> gamma eta_b in e^+e^- annihilation data taken with the CLEO III detector. Using 6 million Upsilon(3S) decays, and assuming Gamma(eta_b) = 10 MeV/c^2, we obtain B(Upsilon(3S) --> gamma eta_b) = (7.1 +- 1.8 +- 1.1) X 10^{-4}, where the first error is statistical and the second is systematic. The statistical significance is about 4 sigma. The mass is determined to be M(eta_b) = 9391.8 +- 6.6 +- 2.0 MeV/c^2, which corresponds to the hyperfine splitting Delta M_{hf}(1S)_b = 68.5 +- 6.6 +- 2.0 MeV/c^2. Using 9 million Upsilon(2S) decays, we place an upper limit on the corresponding Y(2S) decay, B(Y(2S) --> gamma eta_b) < 8.4 X 10^{-4} at 90 % confidence level.

Observation of the hc(1P) Using e+e- Collisions above the DD̄ Threshold

Using 586  pb(-1) of e+ e- collision data at E(c.m.) = 4170  MeV, produced at the Cornell Electron Storage Ring collider and collected with the CLEO-c detector, we observe the process e+ e- → π+ π- h(c)(1P). We measure its cross section to be 15.6±2.3±1.9±3.0  pb, where the third error is due to the external uncertainty on the branching fraction of ψ(2S) → π0 h(c)(1P), which we use for normalization. We also find evidence for e+ e- → ηh(c)(1P) at 4170 MeV at the 3σ level and see hints of a rise in the e+ e- → π+ π- h(c)(1P) cross section at 4260 MeV.

Dalitz plot analysis of Ds+→K+K-π+

We perform a Dalitz plot analysis of about 100,000 Ds+ decays to K+ K- pi+ and measure the complex amplitudes of the intermediate resonances which contribute to this decay mode. We also measure the relative branching fractions of Ds+ -->K+ K+ pi- and Ds+ -->K+ K+ K-. For this analysis we use a 384 fb-1 data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e+e- collider running at center-of-mass energies near 10.58 GeV.We perform a Dalitz plot analysis of about 100 000 Ds+ decays to K+K-π+ and measure the complex amplitudes of the intermediate resonances which contribute to this decay mode. We also measure the relative branching fractions of Ds+→K+K+π- and Ds+→K+K+K-. For this analysis we use a 384 fb-1 data sample, recorded by the BABAR detector at the PEP-II asymmetric-energy e+e- collider running at center-of-mass energies near 10.58 GeV.

Study of ψ(2S) decays to γpp̄, π0pp̄, and ηpp̄, and search for pp̄ threshold enhancements

The decays of {psi}(2S) into {gamma}pp, {pi}{sup 0}pp, and {eta}pp have been studied with the CLEO-c detector using a sample of 24.5x10{sup 6} {psi}(2S) events obtained from e{sup +}e{sup -} annihilations at {radical}(s)=3686 MeV. The data show evidence for the excitation of several N{sup *} resonances in p{pi}{sup 0} and p{eta} channels in {pi}{sup 0}pp and {eta}pp decays, and f{sub 2} states in {gamma}pp decay. Branching fractions for decays of {psi}(2S) to {gamma}pp, {pi}{sup 0}pp, and {eta}pp have been determined. No evidence for pp threshold enhancements was found in the reactions {psi}(2S){yields}Xpp, where X={gamma}, {pi}{sup 0}, {eta}. We do, however, find confirming evidence for a pp threshold enhancement in J/{psi}{yields}{gamma}pp as previously reported by BES.

Updated measurements of absolute

Utilizing the full CLEO-c data sample of 818 pb

D^+

^{-1}

and

of

D^0

e^+e^-