2,482 research outputs found

    INFORMATION SECURITY ASSESSMENT FOR MULTI-AGENT ROBOTIC SYSTEM UNDER THE INFORMATION IMPACT

    Get PDF
    The paper deals with the features of information security guaranteeing of the multi-agent robotic system with self-organizing behavior. The main attention is paid to the possibility of implementing information security threats on the level of interaction between the individual elements. The definitions “information impact” and “disorganization” are introduced for multi-agent robotic system. As a criterion for the system safety state assessment, probability is selected of number of items available at time t for required task execution of multi-agent robotic system, not suffering from the effects of the information impact. A method for estimating the probability of the multi-agent robotic system being in a safe state is proposed. The method is based on mathematical apparatus of Markov chains. Its distinction is the usage of functional dependencies for intensity information impact. The method gives the possibility to identify required characteristics of the individual elements in the early stages of development. Graphs of probability for secure system state of group of elements at different intensities of information impact by intruder and intensities are given, characterizing software and hardware capabilities of element output from the unsafe condition. The system behavior is modeled in the dynamics for different functional dependencies of the information impact intensity. An example of group consisting of four identical elements staying in a safe condition and attacking by three disorganizing elements is shown. Technique of obtaining numerical values for the intensities of information impact at successive instants is revealed

    Evidence for CP Violation in B0 -> D+D- Decays

    Get PDF
    We report measurements of the branching fraction and CP violation parameters in B0 -> D+D- decays. The results are based on a data sample that contains 535 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain [1.97 +- 0.20 (stat) +- 0.20 (syst)] x 10^(-4) for the branching fraction of B0 -> D+D-. The measured values of the CP violation parameters are: S = -1.13 +- 0.37 +- 0.09, A = 0.91 +- 0.23 +- 0.06, where the first error is statistical and the second is systematic. We find evidence of CP violation in B0 -> D+D- at the 4.1 sigma confidence level. While the value of S is consistent with expectations from other measurements, the value of the parameter A favors large direct CP violation at the 3.2 sigma confidence level, in contradiction to Standard Model expectations.Comment: 12 pages, 3 figures, submitted to PR

    Spectral Correlation in Incommensurate Multi-Walled Carbon Nanotubes

    Full text link
    We investigate the energy spectra of clean incommensurate double-walled carbon nanotubes, and find that the overall spectral properties are described by the so-called critical statistics of Anderson metal-insulator transition. In the energy spectra, there exist three different regimes characterized by Wigner-Dyson, Poisson, and semi-Poisson distributions. This feature implies that the electron transport in incommensurate multi-walled nanotubes can be either diffusive, ballistic, or intermediate between them, depending on the position of the Fermi energy.Comment: final version to appear in Phys. Rev. Let

    Determination of the Michel Parameters rho, xi, and delta in tau-Lepton Decays with tau --> rho nu Tags

    Full text link
    Using the ARGUS detector at the e+e−e^+ e^- storage ring DORIS II, we have measured the Michel parameters ρ\rho, Ο\xi, and ΟΎ\xi\delta for τ±→l±ΜΜˉ\tau^{\pm}\to l^{\pm} \nu\bar\nu decays in τ\tau-pair events produced at center of mass energies in the region of the ΄\Upsilon resonances. Using τ∓→ρ∓Μ\tau^\mp \to \rho^\mp \nu as spin analyzing tags, we find ρe=0.68±0.04±0.08\rho_{e}=0.68\pm 0.04 \pm 0.08, Οe=1.12±0.20±0.09\xi_{e}= 1.12 \pm 0.20 \pm 0.09, ΟΎe=0.57±0.14±0.07\xi\delta_{e}= 0.57 \pm 0.14 \pm 0.07, ρΌ=0.69±0.06±0.08\rho_{\mu}= 0.69 \pm 0.06 \pm 0.08, ΟΌ=1.25±0.27±0.14\xi_{\mu}= 1.25 \pm 0.27 \pm 0.14 and ΟΎΌ=0.72±0.18±0.10\xi\delta_{\mu}= 0.72 \pm 0.18 \pm 0.10. In addition, we report the combined ARGUS results on ρ\rho, Ο\xi, and ΟΎ\xi\delta using this work und previous measurements.Comment: 10 pages, well formatted postscript can be found at http://pktw06.phy.tu-dresden.de/iktp/pub/desy97-194.p

    Study of B -> \rho \pi decays at Belle

    Full text link
    This paper describes a study of B meson decays to the pseudoscalar-vector final state \rho\pi using 31.9\times 10^6 B\bar{B} events collected with the Belle detector at KEKB. The branching fractions B(B^+ \to \rho^0\pi^+) = (8.0^{+2.3+0.7}_{-2.0-0.7}) \times 10^{-6} and B(B^0 -> \rho^{+-} \pi^{-+}) = (20.8^{+6.0+2.8}_{-6.3-3.1}) \times 10^{-6} are obtained. In addition, a 90% confidence level upper limit of B(B^0 \to \rho^0\pi^0) < 5.3 \times 10^{-6}is reported.Comment: 14 pages, 3 figures, to be submitted to Phys. Lett.

    Study of the Baryon-Antibaryon Low-Mass Enhancements in Charmless Three-body Baryonic B Decays

    Full text link
    The angular distributions of the baryon-antibaryon low-mass enhancements seen in the charmless three-body baryonic B decays B+ -> p pbar K+, B0 -> p pbar Ks, and B0 -> p Lambdabar pi- are reported. A quark fragmentation interpretation is supported, while the gluonic resonance picture is disfavored. Searches for the Theta+ and Theta++ pentaquarks in the relevant decay modes and possible glueball states G with 2.2 GeV/c2 < M-ppbar < 2.4 GeV/c2 in the ppbar systems give null results. We set upper limits on the products of branching fractions, B(B0 -> Theta+ p)\times B(Theta+ -> p Ks) Theta++ pbar) \times B(Theta++ -> p K+) G K+) \times B(G -> p pbar) < 4.1 \times 10^{-7} at the 90% confidence level. The analysis is based on a 140 fb^{-1} data sample recorded on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.Comment: 14 pages, 13 figure files, update of hep-ex/0409010 for journal submisssio

    Study of the B→X(3872)(→D∗0Dˉ0)KB\to X(3872)(\to D^{*0}\bar D^0)K decay

    Full text link
    We present a study of B→X(3872)KB\to X(3872)K with X(3872) decaying to D∗0Dˉ0D^{*0}\bar D^0 using a sample of 657 million BBˉB\bar B pairs recorded at the ΄(4S)\Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e−e^+e^- collider. Both D∗0→D0ÎłD^{*0}\to D^0\gamma and D∗0→D0π0D^{*0}\to D^0\pi^0 decay modes are used. We find a peak of 50.1−11.1+14.850.1^{+14.8}_{-11.1} events with a mass of (3872.9−0.4−0.5+0.6+0.4)MeV/c2(3872.9^{+0.6 +0.4}_{-0.4 -0.5}){\rm MeV}/c^2, a width of (3.9−1.4−1.1+2.8+0.2)MeV/c2(3.9^{+2.8 +0.2}_{-1.4 -1.1}){\rm MeV}/c^2 and a product branching fraction B(B→X(3872)K)×B(X(3872)→D∗0Dˉ0)=(0.80±0.20±0.10)×10−4{\cal B}(B\to X(3872)K)\times{\cal B}(X(3872)\to D^{*0}\bar D^0)=(0.80\pm0.20\pm0.10)\times10^{-4}, where the first errors are statistical and the second ones are systematic. The significance of the signal is 6.4σ6.4\sigma. The difference between the fitted mass and the D∗0Dˉ0D^{*0}\bar D^0 threshold is calculated to be (1.1−0.4−0.3+0.6+0.1)MeV/c2(1.1^{+0.6 +0.1}_{-0.4 -0.3}){\rm MeV}/c^2. We also obtain an upper limit on the product of branching fractions B(B→Y(3940)K)×B(Y(3940)→D∗0Dˉ0){\cal B}(B\to Y(3940)K)\times{\cal B}(Y(3940)\to D^{*0}\bar D^0) of 0.67×10−40.67\times10^{-4} at 90% CL.Comment: 7 pages, 3 figures, BELLE-CONF-0832 contributed to ICHEP 2008, revised and submitted to Phys. Rev. D R

    Dalitz analysis of B --> K pi psi' decays and the Z(4430)+

    Full text link
    From a Dalitz plot analysis of B --> K pi psi' decays, we find a signal for Z(4430)+ --> pi+ psi' with a mass M= (4443(+15-12)(+19-13))MeV/c^2, width Gamma= (107(+86-43)(+74-56))MeV, product branching fraction BR(B0 --> K- Z(4430)+) x BR(Z(4430)+ --> pi+ psi')= (3.2(+1.8-0.9)(+5.3-1.6)) x 10^{-5}, and significance of 6.4sigma that agrees with previous Belle measurements based on the same data sample. In addition, we determine the branching fraction BR(B^0 --> K*(892)^0 psi')= (5.52(+0.35-0.32)(+0.53-0.58)) x 10^{-4} and the fraction of K*(892)^0 mesons that are longitudinally polarized f_L= 44.8(+4.0-2.7)(+4.0-5.3)%. These results are obtained from a 605fb^{-1} data sample that contains 657 million B-anti-B pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider.Comment: Final version published in PRD(RC

    Measurement of B0→π+π−π+π−B^0\to\pi^+\pi^-\pi^+\pi^- Decays and Search for B0→ρ0ρ0B^0\to\rho^0\rho^0

    Full text link
    We report on a search for the decay B0→ρ0ρ0B^0\to\rho^0\rho^0 and other charmless modes with a π+π−π+π−\pi^+\pi^-\pi^+\pi^- final state, including B0→ρ0π+π−B^0\to\rho^0\pi^+\pi^-, non-resonant B0→4π±B^0\to 4\pi^{\pm}, B0→ρ0f0(980)B^0\to\rho^0f_0(980), B0→f0(980)f0(980)B^0\to f_0(980)f_0(980) and B0→f0(980)π+π−B^0\to f_0(980)\pi^+\pi^-. These results are obtained from a data sample containing 657 million BB‟B \overline B pairs collected with the Belle detector at the KEKB asymmetric-energy e+e−e^+e^- collider. We set an upper limit on B(B0→ρ0ρ0)\mathcal{B}(B^0\to\rho^0\rho^0) of 1.0×10−61.0\times 10^{-6} at the 90% confidence level (C.L.). From our B0→ρ0ρ0B^0\to\rho^0\rho^0 measurement and an isospin analysis, we determine the Cabibbo-Kobayashi-Maskawa phase ϕ2\phi_2 to be 91.7±14.991.7 \pm 14.9 degrees. We find excesses in B0→ρ0π+π−B^0\to \rho^0\pi^+\pi^- and non-resonant B0→4π±B^0\to 4\pi^{\pm} with 1.3σ\sigma and 2.5σ\sigma significance, respectively. The corresponding branching fractions are less than 12.0×10−612.0 \times 10^{-6} and 19.3×10−619.3 \times 10^{-6} at the 90% C.L. In addition, we set 90% C.L. upper limits as follows: B(B0→ρ0f0(980))<0.3×10−6\mathcal{B}(B^0\to\rho^0f_0(980))< 0.3 \times 10^{-6}, B(B0→f0(980)f0(980))<0.1×10−6\mathcal{B}(B^0\to f_0(980)f_0(980))< 0.1 \times 10^{-6}, and B(B0→f0(980)π+π−)<3.8×10−6\mathcal{B}(B^0\to f_0(980)\pi^+\pi^-)< 3.8 \times 10^{-6}.Comment: 6 pages, 2 figures. Submitted to PRD(RC
    • 

    corecore