91,678 research outputs found

    Insurancitis

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    Kepler Fourier concepts: The performance of the Kepler data pipeline

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    Given the extreme precision attainable with the Kepler Space Telescope, the mitigation of instrumental artefacts is very important. In an earlier paper (Murphy 2012), the characteristics of Kepler data were discussed in light of their effect on asteroseismology. We continue this discussion now that data processed with the new PDC-MAP pipeline are publicly available; users should use the latest data reductions available at the Mikulski Archive for Space Telescopes (MAST), not just for PDC, but also for improvements in the attached meta-data. We discuss the injection of noise in the frequency range 0-24 c/d (up to ~277 {\mu}Hz) by the PDC-LS pipeline into ~15 per cent of light-curves.Comment: 4 pages, 7 figures of which 4 are colour. On material presented at the conference "The Modern Era of Helio- and Asteroseismology" held at Obergurgl, Austria, May 2012. Published in AN (Volume 333, Issue 10, Pages 1057-1060

    STS-3/OSS-1 Plasma Diagnostics Package (PDP) measurements of Orbiter transmitter and subsystem electromagnetic interference

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    The plasma diagnostics package receiver system is described to identify the various antennas and to characterize the complement of receivers which cover the frequency range of 30 Hz to 800 Hz and S-band at 2200 + or - 300 MHz. Sample results are presented to show the variability of electromagnetic effects associated with the orbiter and the time variability of these effects. The electric field and magnetic field maximum and minimum field strength spectra observed during the mission at the pallet location are plotted. Values are also derived for the maximum UHF transmitter and S-band transmitter field strengths. Calibration data to convert from the survey plots to actual narrowband and broadband field strengths are listed

    Aerosol particle molecular spectroscopy

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    The molecular spectroscopy of a solution particle by structure resonance modulation spectroscopy is discussed [S. Arnold and A. B. Pluchino, "Infrared Spectrum of a Single Aerosol Particle by Photothermal Modulation of Structure Resonances," Appl. Opt. 21, 4194 (1982); S. Arnold et al., "Molecular Spectroscopy of a Single Aerosol Particle," Opt. Lett. 9, 4 (1984)]. Analytical equations are derived for time dependence of the particle radius as it interacts with a low intensity IR source (<20 mW/cm^2). This formalism is found to be in good agreement with pulsed experiments. Working equations for the spectroscopy are derived for both constant and periodic IR excitation

    Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe

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    The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the proton-to-electron mass ratio, mu, over cosmological time and distance scales. The inversion transitions of ammonia are particularly sensitive to mu compared to molecular rotational transitions. Comparing the available ammonia spectra observed towards the quasar B0218+357 with new, high-quality rotational spectra, we present the first detailed measurement of mu with this technique, limiting relative deviations from the laboratory value to |dmu/mu| < 1.8x10^{-6} (95% confidence level) at approximately half the Universe's current age - the strongest astrophysical constraint to date. Higher-quality ammonia observations will reduce both the statistical and systematic uncertainties in these measurements.Comment: Science, 20th June 2008. 22 pages, 5 figures (12 EPS files), 2 tables, including Supporting Online Material; v2: Corrected reference for laboratory mu-variation bound

    Rose of the Hawthornes

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