Using 281 pb{sup -1} of data collected with the CLEO-c detector, we report on first observations and measurements of Cabibbo-suppressed decays of D mesons in the following six decay modes: {pi}{sup ...+}{pi}{sup -}{pi}{sup 0}{pi}{sup 0}, {pi}{sup +}{pi}{sup +}{pi}{sup -}{pi}{sup -}{pi}{sup 0}, {pi}{sup +}{pi}{sup 0}{pi}{sup 0}, {pi}{sup +}{pi}{sup +}{pi}{sup -}{pi}{sup 0}, {eta}{pi}{sup 0}, and {omega}{pi}{sup +}{pi}{sup -}. Improved branching fraction measurements in eight other multipion decay modes are also presented. The measured D{yields}{pi}{pi} rates allow us to extract the ratio of isospin amplitudes A({delta}I=3/2)/A({delta}I=1/2)=0.420{+-}0.014(stat){+-}0.016(syst) and the strong phase shift of {delta}{sub I}=(86.4{+-}2.8{+-}3.3) deg., which is quite large and now more precisely determined.
We have studied the inclusive photon spectra in Upsilon(2S) and Upsilon(3S) decays using a large statistics data sample obtained with the CLEO III detector. We present the most precise measurements ...of electric dipole (E1) photon transition rates and photon energies for Upsilon(2S) --> gammachi(bJ)(1P) and Upsilon(3S) --> gammachi(bJ)(2P) (J = 0, 1, 2). We measure the rate for a rare E1 transition Upsilon(3S) --> gammachi(b0)(1P) for the first time. We also set upper limits on the rates for the hindered magnetic dipole (M1) transitions to the eta(b)(1S) and eta(b)(2S) states.
Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+decays to K0e+ve, ...pi0e+ve, K*0e+ve, and p0e+ve, and the first observation and absolute branching fraction measurement of D+ --> omega e+ve. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays.
Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high ...statistic differential cross sections are reported for the semiexclusive reaction ν_{μ}A→μ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{μ} beam with ⟨E_{ν}⟩≈6 GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.
We report the first detailed comparisons of the rates and spectra of neutral-current neutrino interactions at two widely separated locations. A depletion in the rate at the far site would indicate ...mixing between nu(mu) and a sterile particle. No anomalous depletion in the reconstructed energy spectrum is observed. Assuming oscillations occur at a single mass-squared splitting, a fit to the neutral- and charged-current energy spectra limits the fraction of nu(mu) oscillating to a sterile neutrino to be below 0.68 at 90% confidence level. A less stringent limit due to a possible contribution to the measured neutral-current event rate at the far site from nu(e) appearance at the current experimental limit is also presented.
Separate samples of charged-current pion production events representing two semi-inclusive channels νμ−CC(π+) and ν¯μ−CC(π0) have been obtained using neutrino and antineutrino exposures of the ...MINERvA detector. Distributions in kinematic variables based upon μ±-track reconstructions are analyzed and compared for the two samples. The differential cross sections for muon production angle, muon momentum, and four-momentum transfer Q2 are reported, and cross sections versus neutrino energy are obtained. Comparisons with predictions of current neutrino event generators are used to clarify the role of the Δ(1232) and higher-mass baryon resonances in CC pion production and to show the importance of pion final-state interactions. For the νμ−CC(π+) ν¯μ−CC(π0) sample, the absolute data rate is observed to lie below (above) the predictions of some of the event generators by amounts that are typically 1-to- 2σ. However the generators are able to reproduce the shapes of the differential cross sections for all kinematic variables of either data set.
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