Search for CP violation in τ → ππ0ντ decay
Physical Review D 64:9 (2001)
Abstract:
We search for CP nonconservation in the decays of τ leptons produced via e+e- annihilation at √s ∼ 10.6 GeV. The method uses correlated decays of pairs of τ leptons, each decaying to the ππ0ντ final state. The search is done within the framework of a model with a scalar boson exchange. In an analysis of a data sample corresponding to 12.2×106 produced τ pairs collected with the CLEO detector, we find no evidence of violation of CP symmetry. We obtain a limit on the imaginary part of the coupling constant parametrizing the relative contribution of diagrams that would lead to CP violation to be -0.046Improved upper limits on the flavor-changing neutral current decays B → Kℓ+ℓ- and B → K* (892)ℓ+ℓ-
Physical Review Letters 87:18 (2001) 1818031-1818035
Abstract:
The flavor-changing neutral current (FCNC) decay was studied using Monte Carlo simulations to determine the efficiency for detecting the signal modes. The upper limits on branching fractions were obtained and no indication of a signal were obtained for the decay. Systematic and statistical errors for the process were calculated numerically.Search for the decay upsilon(1S) --> gammaeta(').
Phys Rev Lett 87:14 (2001) 141801
Abstract:
We report on a search for the radiative decay Upsilon(1S)-->gammaeta(') in 61.3 pb(-1) of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Three decay chains were investigated, all involving eta(')-->pi(+)pi(-)eta, followed by eta-->gammagamma, eta-->pi(0)pi(0)pi(0), or eta-->pi(+)pi(-)pi(0). We find no candidate events in any of the three cases and set a combined upper limit of 1.6x10(-5) at 90% C.L., significantly smaller than the previous limit. We compare our result to other radiative Upsilon decays, to radiative J/psi decays, and to theoretical predictions.Search for the decay Y(1S) → γη′
Physical Review Letters 87:14 (2001)
Abstract:
A study was carried out to search for the decay Υ → γη' with the decay mode η' → ηπ+π- and three decay modes of the η. Using simple, loose selection criteria, no candidates were found and the 90%C C.L. limit of B(Υ → γη') 1.6 × 10-5 was set.Rate measurement of D(0)-->K+pi(-)pi(0) and constraints on D(0) -- D(0) mixing.
Phys Rev Lett 87:7 (2001) 071802