arXiv subjects
Publications and source records attributed to G. Bonvicini.
We have searched for CP-violating asymmetries in neutral charm meson decays in 13.7 fb^-1 of e^+e^- collision data at sqrt{s} = 10.6 GeV with the CLEO detector. The measured asymmetries in the rate of D0 and D0bar decays to K0sPi0, Pi0Pi0 and K0sK0s final states are (+0.1 +- 1.3)%, (+0.1 +- 4.8)% and (-23 +- 19)%, respectively.
We present a search for direct CP violation in B+- -> J/psi K+- and B+- -> psi(2S) K+- decays. In a sample of 9.7 million B meson pairs collected with the CLEO detector, we have fully reconstructed 534 B+- -> J/psi K+- and 120 B+- -> psi(2S) K+- decays with very low background. We have measured the CP-violating charge asymmetry to be (+1.8+-4.3[stat]+-0.4[syst])% for B+- -> J/psi K+- and (+2.0+-9.1[stat]+-1.0[syst])% for B+- -> psi(2S) K+-.
We report measurements of the $D^0, D^+$, and $D^+_s$ meson lifetimes using $3.7 fb^{-1}$ of e^+e^- annihilation data collected near the $Υ(4S)$ resonance with the CLEO detector. The lifetimes of the $D^0, D^+$, and $D^+_s$ mesons are measured to be $408.5 \pm 4.1 ^{+3.5}_{-3.4} fs, 1033.6 \pm 22.1 ^{+9.9}_{-12.7} fs$, and $486.3 \pm 15.0 ^{+4.9}_{-5.1} fs$, respectively. The precisions of the charm meson lifetimes reported here are comparable to those of the best previous measurements, and the systematic errors are very different. In a single experiment we find that the ratio of the $D^+_s$ and $D^0$ lifetimes differs from one by more than 4.5 standard deviations.
A novel method to measure the beam-beam interaction in e+e- colliders is presented.
The relation between beamstrahlung observables and beam-beam topologies is discussed.
The value of the $b$-baryon polarization can be extracted from inclusive data at LEP with better than 10\% precision based on current statistics. We present a new variable by which to measure the polarization, which is the ratio of the average electron energy to the average neutrino energy. This variable is both sensitive to polarization and insensitive to fragmentation uncertainties.