EP-1518: Evaluation of dynamic delivery quality assurance process for internal target based RapidArc

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Chemical Synthesis of PEDOT–Au Nanocomposite

In this work, gold-incorporated polyethylenedioxythiophene nanocomposite material has been synthesized chemically, employing reverse emulsion polymerization method. Infrared and Raman spectroscopic studies revealed that the polymerization of ethylenedioxythiophene leads to the formation of polymer polyethylenedioxythiophene incorporating gold nanoparticles. Scanning electron microscope studies showed the formation of polymer nanorods of 50–100 nm diameter and the X-ray diffraction analysis clearly indicates the presence of gold nanoparticles of 50 nm in size

Component-based modeling of PEM fuel cells with bond graphs

A polymer electrolyte membrane (PEM) fuel cell is a power generation device that transforms chemical energy contained within hydrogen and oxygen gases into useful electricity. The performance of a PEMFC unit is governed by three interdependent physical phenomena: heat, mass, and charge transfer. When modelling such a multi-physical system it is advantageous to use an approach capable of representing all the processes in a unified fashion. This paper presents a component-based model of PEMFCs developed using the bond graph (BG) technique in Modelica language. The basics of the BG method are outlined and a number of relevant publications are reviewed. Model assumptions and necessary equations for each fuel cell component are outlined. The overall model is constructed from a set of bond-graphic blocks within thermal, pneumatic and electrical domains. The model output was compared with the experimental data gathered from a two-cell stack and demonstrated a good accuracy in predicting system behaviour. In the future the designed model will be used for fuel cell reliability studies

B→KB\to K Transition Form Factor up to O(1/mb2){\cal O}(1/m^2_b) within the kTk_T Factorization Approach

In the paper, we apply the $k_T$ factorization approach to deal with the $B\to K$ transition form factor $F^{B\to K}_{+,0}(q^2)$ in the large recoil regions. The B-meson wave functions $\Psi_B$ and $\bar\Psi_B$ that include the three-particle Fock states' contributions are adopted to give a consistent PQCD analysis of the form factor up to ${\cal O} (1/m^2_b)$. It has been found that both the wave functions $\Psi_B$ and $\bar\Psi_B$ can give sizable contributions to the form factor and should be kept for a better understanding of the $B$ meson decays. Then the contributions from different twist structures of the kaon wavefunction are discussed, including the $SU_f(3)$-breaking effects. A sizable contribution from the twist-3 wave function $\Psi_p$ is found, whose model dependence is discussed by taking two group of parameters that are determined by different distribution amplitude moments obtained in the literature. It is also shown that $F^{B\to K}_{+,0}(0)=0.30\pm0.04$ and $[F^{B\to K}_{+,0}(0)/F^{B\to \pi}_{+,0}(0)]=1.13\pm0.02$, which are more reasonable and consistent with the light-cone sum rule results in the large recoil regions.Comment: 22 pages and 6 figure

Search for the Flavor-Changing Neutral Current Decay D0→μ+μ−D^0 \to \mu^+\mu^- with the HERA-B Detector

We report on a search for the flavor-changing neutral current decay $D^0 \to \mu^+\mu^-$ using $50 \times 10^6$ events recorded with a dimuon trigger in interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find no evidence for such decays and set a 90% confidence level upper limit on the branching fraction $Br(D^0 \to \mu^+\mu^-) <2.0 \times 10^{-6}$.Comment: 17 pages, 4 figures (of which 1 double), paper to be submitted to Physics Letters

Observation of a Narrow Resonance of Mass 2.46 GeV/c^2 Decaying to D_s^*+ pi^0 and Confirmation of the D_sJ^* (2317) State

Using 13.5 inverse fb of e+e- annihilation data collected with the CLEO II detector we have observed a narrow resonance in the Ds*+pi0 final state, with a mass near 2.46 GeV. The search for such a state was motivated by the recent discovery by the BaBar Collaboration of a narrow state at 2.32 GeV, the DsJ*(2317)+ that decays to Ds+pi0. Reconstructing the Ds+pi0 and Ds*+pi0 final states in CLEO data, we observe peaks in both of the corresponding reconstructed mass difference distributions, dM(Dspi0)=M(Dspi0)-M(Ds) and dM(Ds*pi0)=M(Ds*pi0)-M(Ds*), both of them at values near 350 MeV. We interpret these peaks as signatures of two distinct states, the DsJ*(2317)+ plus a new state, designated as the DsJ(2463)+. Because of the similar dM values, each of these states represents a source of background for the other if photons are lost, ignored or added. A quantitative accounting of these reflections confirms that both states exist. We have measured the mean mass differences = 350.0 +/- 1.2 [stat] +/- 1.0 [syst] MeV for the DsJ*(2317) state, and = 351.2 +/- 1.7 [stat] +/- 1.0 [syst] MeV for the new DsJ(2463)+ state. We have also searched, but find no evidence, for decays of the two states via the channels Ds*+gamma, Ds+gamma, and Ds+pi+pi-. The observations of the two states at 2.32 and 2.46 GeV, in the Ds+pi0 and Ds*+pi0 decay channels respectively, are consistent with their interpretations as (c anti-strange) mesons with orbital angular momentum L=1, and spin-parities of 0+ and 1+.Comment: 16 pages postscript, also available through http://w4.lns.cornell.edu/public/CLNS, version to be published in Physical Review D; minor modifications and fixes to typographical errors, plus an added section on production properties. The main results are unchanged; they supersede those reported in hep-ex/030501

Measurement of Branching Fractions and Charge Asymmetries for Two-Body B Meson Decays with Charmonium

We report branching fractions and charge asymmetries for exclusive decays of charged and neutral B mesons to two-body final states containing a charmonium meson, J/psi or psi(2S). This result is based on a 29.4 fb^{-1} data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e+e- collider.Comment: 13 pages, 5 figures, revte

Measurement of the Charge Asymmetry in B→K∗(892)±π∓B\to K^* (892)^{\pm}\pi^{\mp}

We report on a search for a CP-violating asymmetry in the charmless hadronic decay B -> K*(892)+- pi-+, using 9.12 fb^-1 of integrated luminosity produced at \sqrt{s}=10.58 GeV and collected with the CLEO detector. We find A_{CP}(B -> K*(892)+- pi-+) = 0.26+0.33-0.34(stat.)+0.10-0.08(syst.), giving an allowed interval of [-0.31,0.78] at the 90% confidence level.Comment: 7 pages postscript, also available through http://w4.lns.cornell.edu/public/CLNS, submitted to PR

Study of the q^2-Dependence of B --> pi ell nu and B --> rho(omega)ell nu Decay and Extraction of |V_ub|

We report on determinations of |Vub| resulting from studies of the branching fraction and q^2 distributions in exclusive semileptonic B decays that proceed via the b->u transition. Our data set consists of the 9.7x10^6 BBbar meson pairs collected at the Y(4S) resonance with the CLEO II detector. We measure B(B0 -> pi- l+ nu) = (1.33 +- 0.18 +- 0.11 +- 0.01 +- 0.07)x10^{-4} and B(B0 -> rho- l+ nu) = (2.17 +- 0.34 +0.47/-0.54 +- 0.41 +- 0.01)x10^{-4}, where the errors are statistical, experimental systematic, systematic due to residual form-factor uncertainties in the signal, and systematic due to residual form-factor uncertainties in the cross-feed modes, respectively. We also find B(B+ -> eta l+ nu) = (0.84 +- 0.31 +- 0.16 +- 0.09)x10^{-4}, consistent with what is expected from the B -> pi l nu mode and quark model symmetries. We extract |Vub| using Light-Cone Sum Rules (LCSR) for 0<= q^2<16 GeV^2 and Lattice QCD (LQCD) for 16 GeV^2 <= q^2 < q^2_max. Combining both intervals yields |Vub| = (3.24 +- 0.22 +- 0.13 +0.55/-0.39 +- 0.09)x10^{-3}$ for pi l nu, and |Vub| = (3.00 +- 0.21 +0.29/-0.35 +0.49/-0.38 +-0.28)x10^{-3} for rho l nu, where the errors are statistical, experimental systematic, theoretical, and signal form-factor shape, respectively. Our combined value from both decay modes is |Vub| = (3.17 +- 0.17 +0.16/-0.17 +0.53/-0.39 +-0.03)x10^{-3}.Comment: 45 pages postscript, also available through http://w4.lns.cornell.edu/public/CLNS, submitted to PR

Search for CP Violation in D^0--> K_S^0 pi^+pi^-

We report on a search for CP violation in the decay of D0 and D0B to Kshort pi+pi-. The data come from an integrated luminosity of 9.0 1/fb of e+e- collisions at sqrt(s) ~ 10 GeV recorded with the CLEO II.V detector. The resonance substructure of this decay is well described by ten quasi-two-body decay channels (K*-pi+, K*0(1430)-pi+, K*2(1430)-pi+, K*(1680)-pi+, Kshort rho, Kshort omega, Kshort f0(980), Kshort f2(1270), Kshort f0(1370), and the ``wrong sign'' K*+ pi-) plus a small non-resonant component. We observe no evidence for CP violation in the amplitudes and phases that describe the decay D0 to K_S^0 pi+pi-.Comment: 10 pages, 3 figures, also available at http://w4.lns.cornell.edu/public/CLNS/, submitted to PR