3,224 research outputs found

    Temperature measurement and calibration in small punch creep testing machines and equipment

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    Serious lifetime estimation of machinery working in the power industry is conditioned by knowledge of an actual state of used construction materials. Determination of degradation degree by detection of mechanical properties of materials at machine parts used in operating conditions without the necessity of stopping operation of the apparatus and machine component disintegration in the past has led to the development of miniaturized test specimens associated with the emergence of special test procedures and methods. One of these methods is the small punch test (SPT) performed at room, low or elevated temperatures. Just testing temperature is one of the most important test parameters. The accuracy of measurement of this variable is a basic condition of repeatability, compatibility and comparability of the measured testing results. Very small specimen size, the way how it is stored in the heating system, the prescribed tolerance of measurement accuracy determines the way of measuring and controlling its temperature. One possible way of measuring specimen temperature is using a thermocouple directly touching its surface in the test process. However, this method is influenced by the unequal heat conduction between the specimen and the punch with the push pin in an upper direction and the cartridge sitting in the rod within the lower direction. How to determine the real specimen temperature in control systems of SPUTT500 testing machine is the subject of this paper

    Resolution Studies on Silicon Strip Sensors with fine Pitch

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    In June 2008 single-sided silicon strip sensors with 50 μ\mum readout pitch were tested in a highly energetic pion beam at the SPS at CERN. The purpose of the test was to evaluate characteristic detector properties by varying the strip width and the number of intermediate strips. The experimental setup and first results for the spatial resolution are discussed.Comment: proceeding of the International Linear Collider Workshop 2008 (LCWS08); corrected typos, added reference for section

    ATLAS silicon module assembly and qualification tests at IFIC Valencia

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    ATLAS experiment, designed to probe the interactions of particles emerging out of proton proton collisions at energies of up to 14 TeV, will assume operation at the Large Hadron Collider (LHC) at CERN in 2007. This paper discusses the assembly and the quality control tests of forward detector modules for the ATLAS silicon microstrip detector assembled at the Instituto de Fisica Corpuscular (IFIC) in Valencia. The construction and testing procedures are outlined and the laboratory equipment is briefly described. Emphasis is given on the module quality achieved in terms of mechanical and electrical stability.Comment: 23 pages, 38 EPS figures, uses JINST LaTeX clas

    Experimental Tests of Neutron Shielding for the ATLAS Forward Region

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    Experimental tests devoted to the optimization of the neutron shielding for the ATLAS forward region were performed at the CERN-PS with a 4 GeV/c proton beam. Spectra of fast neutrons, slow neutrons and gamma rays escaping a block of iron (40×\times40×\times80 cm3^3) shielded with different types of neutron and gamma shields (pure polyethylene - PE, borated polyethylene - BPE, lithium filled polyethylene - LiPE, lead, iron) were measured by means of plastic scintillators, a Bonner spectrometer, a HPGe detector and a slow neutron detector. Effectiveness of different types of shielding agaisnt neutrons and γ\gamma-rays were compared. The idea of a segmented outer layer shielding (iron, BPE, iron, LiPE) for the ATLAS Forward Region was also tested

    Observation of D0Dˉ0D^0-\bar{D}^0 Mixing in e+ee^+e^- Collisions

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    We observe D0Dˉ0D^0-\bar{D}^0 mixing in the decay D0K+πD^0\rightarrow K^+\pi^- using a data sample of integrated luminosity 976 fb1^{-1} collected with the Belle detector at the KEKB e+ee^+e^- asymmetric-energy collider. We measure the mixing parameters x2=(0.09±0.22)×103{x'}^2 = (0.09\pm0.22)\times 10^{-3} and y=(4.6±3.4)×103y' = (4.6\pm3.4)\times 10^{-3} and the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates RD=(3.53±0.13)×103R_D = (3.53\pm0.13)\times 10^{-3}, where the uncertainties are statistical and systematic combined. Our measurement excludes the no-mixing hypothesis at the 5.1 standard deviation level.Comment: 6 pages, 4 figure

    Search for the decay B+K0K+B^+\rightarrow\overline{K}{}^{*0}K^{*+} at Belle

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    We report a search for the rare charmless decay B+K0K+B^+\rightarrow\overline{K}{}^{*0}K^{*+} using a data sample of 772×106772\times10^6 BBˉB\bar{B} pairs collected at the Υ(4S)\Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ee^+e^- collider. No statistically significant signal is found and a 90% confidence-level upper limit is set on the decay branching fraction as B(B+K0K+)<1.31×106 \mathcal{B}(B^+\rightarrow\overline{K}{}^{*0}K^{*+}) <1.31\times 10^{-6}.Comment: 8 pages, 3 figures, submitted to PRD(RC

    Evidence for a new resonance and search for the Y(4140) in γγϕJ/ψ\gamma \gamma \to \phi J/\psi

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    The process \gamma \gamma \to \phi \jpsi is measured for \phi \jpsi masses between threshold and 5 GeV/c2{\it c}^2, using a data sample of 825 fb1^{-1} collected with the Belle detector. A narrow peak of 8.83.2+4.28.8^{+4.2}_{-3.2} events, with a significance of 3.2 standard deviations including systematic uncertainty, is observed. The mass and natural width of the structure (named X(4350)) are measured to be (4350.65.1+4.6(stat)±0.7(syst))MeV/c2(4350.6^{+4.6}_{-5.1}(\rm{stat})\pm 0.7(\rm{syst})) \hbox{MeV}/{\it c}^2 and (139+18(stat)±4(syst))MeV(13^{+18}_{-9}(\rm{stat})\pm 4(\rm{syst})) \hbox{MeV}, respectively. The product of its two-photon decay width and branching fraction to \phi\jpsi is (6.72.4+3.2(stat)±1.1(syst))eV(6.7^{+3.2}_{-2.4}(\rm{stat}) \pm 1.1(\rm{syst})) \hbox{eV} for JP=0+J^P=0^+, or (1.50.6+0.7(stat)±0.3(syst))eV(1.5^{+0.7}_{-0.6}(\rm{stat}) \pm 0.3(\rm{syst})) \hbox{eV} for JP=2+J^P=2^+. No signal for the Y(4140)\to \phi \jpsi structure reported by the CDF Collaboration in B\to K^+ \phi \jpsi decays is observed, and limits of \Gamma_{\gamma \gamma}(Y(4140)) \BR(Y(4140)\to\phi \jpsi)<41 \hbox{eV} for JP=0+J^P=0^+ or <6.0eV<6.0 \hbox{eV} for JP=2+J^P=2^+ are determined at the 90% C.L. This disfavors the scenario in which the Y(4140) is a Ds+DsD_{s}^{\ast+} {D}_{s}^{\ast-} molecule.Comment: 9 pages, 3 figures, publication in Phys. Rev. Lett. 104, 112004, 201
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