A fast MPP algorithm for Ising spin exchange simulations

A very efficient massively parallel processor (MPP) algorithm is described for performing one important class of Ising spin simulations. Results and physical significance of MPP calculations using the method described is discussed elsewhere. A few comments, however, are made on the problem under study and results so far are reported. Ted Einstein provided guidance in interpreting the initial results and in suggesting calculations to perform

Branching Fractions for chi_cJ -\u3e p p-bar pi^0, p p-bar eta, and p p-bar omega

Using a sample of 25.9 million psi(2S) decays acquired with the CLEO-c detector at the CESR e^+e^- collider, we report branching fractions for the decays chi_cJ -\u3e p p-bar pi^0, p p-bar eta, and p p-bar omega, with J=0,1,2. Our results for B(chi_cJ-\u3e p p-bar pi^0) and B(chi_cJ-\u3e p p-bar eta) are consistent with, but more precise than, previous measurements. Furthermore, we include the first measurement of B(chi_cJ-\u3e p p-bar omega)

Observation of the Dalitz Decay Ds*+ → Ds*+ e+e-

Using 586 \textrm{pb}^{-1} of e^{+}e^{-} collision data acquired at \sqrt{s}=4.170 GeV with the CLEO-c detector at the Cornell Electron Storage Ring, we report the first observation of D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-} with a significance of 5.3 \sigma. The ratio of branching fractions \calB(D_{s}^{*+} \to D_{s}^{+} e^{+} e^{-}) / \calB(D_{s}^{*+} \to D_{s}^{+} \gamma) is measured to be [ 0.72^{+0.15}_{-0.13} (\textrm{stat}) \pm 0.10 (\textrm{syst})]%, which is consistent with theoretical expectations

Determination of f_s/f_d for 7 TeV pp Collisions and a Measurement of the Branching Fraction of the Decay Bd-\u3eD-K+

The relative abundance of the three decay modes B_d \to D^- K^+, B_d \to D^- \pi^+ and B_s \to D_s^- \pi^+ produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35 pb^{-1}. The branching fraction of B_d \to D^- K^+ is found to be \cal B (B_d \to D^- K^+) = (2.01 \pm 0.18^{\textrm{stat}} \pm 0.14^{\textrm{syst}})\times 10^{-4}. The ratio of fragmentation fractions \fsfdt is determined through the relative abundance of B_s \to D_s^- \pi^+ to B_d \to D^- K^+ and B_d \to D^-\pi^+, leading to f_s/f_d = 0.253 \pm 0.017 \pm 0.017 \pm 0.020, where the uncertainties are statistical, systematic, and theoretical respectively

Study of Ψ(2S) Decays to γpp, π0pp and η pp and Search for pp Threshold Enhancements

The decays of psi(2S) into gamma p bar{p}, pi^0 p bar{p} and eta p bar{p} have been studied with the CLEO-c detector using a sample of 24.5 million psi(2S) events obtained from e^+e^- annihilations at sqrt{s} = 3686 MeV. The data show evidence for the excitation of several N^* resonances in p pi^0 and p eta channels in pi^0 p bar{p} and eta p bar{p} decays, and f_2 states in gamma p bar{p} decay. Branching fractions for decays of psi(2S) to gamma p bar{p}, pi^0 p bar{p} and eta p bar{p} have been determined. No evidence for p bar{p} threshold enhancements was found in the reactions psi(2S)-\u3e X p bar{p}, where X = gamma, pi^0, eta. We do, however, find confirming evidence for a p bar{p} threshold enhancement in J/psi-\u3e gamma p bar{p} as previously reported by BES

Observation of the Hc(1P) Using e+e- Collisions Above DD Threshold

Using 586pb^-1 of e^+e^- collision data at E_CM = 4170MeV, produced at the CESR collider and collected with the CLEO-c detector, we observe the process e^+e^- --\u3e pi^+ pi^- h_c(1P). We measure its cross section to be 15.6+-2.3+-1.9+-3.0pb, where the third error is due to the external uncertainty on the branching fraction of psi(2S) --\u3e pi^0 h_c(1P), which we use for normalization. We also find evidence for e^+e^- --\u3e eta h_c(1P) at 4170MeV at the 3sigma level, and see hints of a rise in the e^+e^- --\u3e pi^+ pi^- h_c(1P) cross section at 4260MeV

Prompt K0S Production in pp Collisions at √s=0.9 TeV

The production of K_short mesons in pp collisions at a centre-of-mass energy of 0.9 TeV is studied with the LHCb detector at the Large Hadron Collider. The luminosity of the analysed sample is determined using a novel technique, involving measurements of the beam currents, sizes and positions, and is found to be 6.8 +/- 1.0 microbarn^-1. The differential prompt K_short production cross-section is measured as a function of the K_short transverse momentum and rapidity in the region 0 \u3c pT \u3c 1.6 GeV/c and 2.5 \u3c y \u3c 4.0. The data are found to be in reasonable agreement with previous measurements and generator expectations

Performance of the CLEO III LiF-TEA Ring Imaging Cherenkov Detector in a High Energy Muon Beam

The CLEO III Ring Imaging Cherenkov detector uses LiF radiators to generate Cherenkov photons which are then detected by proportional wire chambers using a mixture of CH$_4$ and TEA gases. The first two photon detector modules which were constructed, were taken to Fermilab and tested in a beam dump that provided high momentum muons. We report on results using both plane and sawtooth shaped radiators. Specifically, we discuss the number of photoelectrons observed per ring and the angular resolution. The particle separation ability is shown to be sufficient for the physics of CLEO III

Measurement of Measurement of V 0 Production Ratios in pp Collisions at ps = 0.9 and 7TeV

The \bar{\Lambda} / \Lambda and \bar{\Lambda} / K^0_\mathrm{S} production ratios are measured by the LHCb detector from 0.3\,\mathrm{nb}^{-1} of pp collisions delivered by the LHC at \sqrt{s} = 0.9\,TeV and 1.8\,\mathrm{nb}^{-1} at \sqrt{s} = 7\,TeV. Both ratios are presented as a function of transverse momentum, p_\mathrm{T}, and rapidity, y, in the ranges {0.15 \u3c p_\mathrm{T} \u3c 2.50\,\mathrm{GeV}/c} and {2.0