4,305 research outputs found

    Abrupt and gradual changes of information through the Kane solid state computer

    Full text link
    The susceptibility of the transformed information to the filed and system parameters is investigated for the Kane solid state computer. It has been shown, that the field polarization and the initial state of the system play the central roles on the abrupt and gradual quench of the purity and the fidelity. If the field and the initial state are in different polarizations, then the purity and the fidelity decrease abruptly, while for the common polarization the decay is gradual and smooth. For some class of initial states one can send the information without any loss. Therefore, by controlling on the devices one can increase the time of safe communication, reduce the amount of exchange information between the state and its environment and minimize the purity decrease rate

    Out of plane analysis for composite structures

    Get PDF
    Simple two dimensional analysis techniques were developed to aid in the design of strong joints for integrally stiffened/bonded composite structures subjected to out of plane loads. It was found that most out of plane failures were due to induced stresses arising from rapid changes in load path direction or geometry, induced stresses due to changes in geometry caused by buckling, or direct stresses produced by fuel pressure or bearing loads. While the analysis techniques were developed to address a great variety of out of plane loading conditions, they were primarily derived to address the conditions described above. The methods were developed and verified using existing element test data. The methods were demonstrated using the data from a test failure of a high strain wingbox that was designed, built, and tested under a previous program. Subsequently, a set of design guidelines were assembled to assist in the design of safe, strong integral composite structures using the analysis techniques developed

    Strong Lens Models for 37 Clusters of Galaxies from the SDSS Giant Arcs Survey

    Full text link
    We present strong gravitational lensing models for 37 galaxy clusters from the SDSS Giant Arcs Survey. We combine data from multi-band Hubble Space Telescope WFC3imaging, with ground-based imaging and spectroscopy from Magellan, Gemini, APO, and MMT, in order to detect and spectroscopically confirm new multiply-lensed background sources behind the clusters. We report spectroscopic or photometric redshifts of sources in these fields, including cluster galaxies and background sources. Based on all available lensing evidence, we construct and present strong lensing mass models for these galaxy clusters.Comment: 53 pages; submitted to ApJ

    Direct carrier detection by in situ suppression hybridization with cosmid clones of the Duchenne/Becker muscular dystrophy locus

    Get PDF
    A basic problem in genetic counseling of families with Duchenne/Becker muscular dystrophy (DMD/BMD) concerns the carrier status of female relatives of an affected male. In about 60% of these patients, deletions of one or more exons of the dystrophin gene can be identified. These deletions preferentially include exon 45, which can be detected by multiplex polymerase chain reaction (PCR) and Southern blot analysis of genomic cosmid clones that map to this critical region. As a new approach for definitive carrier detection, we have performed chromosomal in situ suppression (CISS) hybridization with these cosmid clones in female relatives of four unrelated patients. In normal females, most metaphases showed signals on both×chromosomes, whereas only one×chromosome was labeled in carriers. Our results demonstrate that CISS hybridization can define the carrier status in female relatives of DMD patients exhibiting a deletion in the dystrophin gene

    Lens Model and Time Delay Predictions for the Sextuply Lensed Quasar SDSS J2222+2745

    Full text link
    SDSS J2222+2745 is a galaxy cluster at z=0.49, strongly lensing a quasar at z=2.805 into six widely separated images. In recent HST imaging of the field, we identify additional multiply lensed galaxies, and confirm the sixth quasar image that was identified by Dahle et al. (2013). We used the Gemini North telescope to measure a spectroscopic redshift of z=4.56 of one of the secondary lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image of the quasar host and a second lensed galaxy at z=2.3. This second galaxy also appears in absorption in our Gemini spectra of the lensed quasar, at a projected distance of 34 kpc. Our model is in agreement with the recent time delay measurements of Dahle et al. (2015), who found tAB=47.7+/-6.0 days and tAC=-722+/-24 days. We use the observed time delays to further constrain the model, and find that the model-predicted time delays of the three faint images of the quasar are tAD=502+/-68 days, tAE=611+/-75 days, and tAF=415+/-72 days. We have initiated a follow-up campaign to measure these time delays with Gemini North. Finally, we present initial results from an X-ray monitoring program with Swift, indicating the presence of hard X-ray emission from the lensed quasar, as well as extended X-ray emission from the cluster itself, which is consistent with the lensing mass measurement and the cluster velocity dispersion.Comment: 16 pages, 11 figures; submitted to Ap

    Determination of Resistance Parameters of Contaminated Compacted Tropical Soils in the State of Rio de Janeiro

    Full text link
    Direct shear (DS) tests with controlled shear rates were performed in two soils from the Baixada Fluminense region, in the city of São João do Meriti – Rio de Janeiro, Brazil. The first soil characterized as Inorganic Clay of high plasticity (CH) was located in a hillside region. The second soil characterized as medium plasticity clay (CL) was located in a central region of the studied area with a slight slope. The soils in question are deposited on non-compacted soft soil with the addition of Municipal Solid Waste (MSW). Both samples of compacted soil were excavated at a depth of 1.0 m, and undisturbed samples were collected. In addition to the previously mentioned tests, oedometric tests and soil physical classification tests were carried out to evaluate geotechnical parameters. In both tests the shear rate of 0.043 mm / min was adopted. The tests presented coherent results with probabilistic accuracy greater than 95% inreliability compared to three tests with compacted tropical soils

    Optimal refrigerator

    Full text link
    We study a refrigerator model which consists of two nn-level systems interacting via a pulsed external field. Each system couples to its own thermal bath at temperatures ThT_h and TcT_c, respectively (θTc/Th<1\theta\equiv T_c/T_h<1). The refrigerator functions in two steps: thermally isolated interaction between the systems driven by the external field and isothermal relaxation back to equilibrium. There is a complementarity between the power of heat transfer from the cold bath and the efficiency: the latter nullifies when the former is maximized and {\it vice versa}. A reasonable compromise is achieved by optimizing the product of the heat-power and efficiency over the Hamiltonian of the two system. The efficiency is then found to be bounded from below by ζCA=11θ1\zeta_{\rm CA}=\frac{1}{\sqrt{1-\theta}}-1 (an analogue of the Curzon-Ahlborn efficiency), besides being bound from above by the Carnot efficiency ζC=11θ1\zeta_{\rm C} = \frac{1}{1-\theta}-1. The lower bound is reached in the equilibrium limit θ1\theta\to 1. The Carnot bound is reached (for a finite power and a finite amount of heat transferred per cycle) for lnn1\ln n\gg 1. If the above maximization is constrained by assuming homogeneous energy spectra for both systems, the efficiency is bounded from above by ζCA\zeta_{\rm CA} and converges to it for n1n\gg 1.Comment: 12 pages, 3 figure

    Spatially Resolved Patchy Lyman-α\alpha Emission Within the Central Kiloparsec of a Strongly Lensed Quasar Host Galaxy at z = 2.8

    Get PDF
    We report the detection of extended Lyman-α\alpha emission from the host galaxy of SDSS~J2222+2745, a strongly lensed quasar at z=2.8z = 2.8. Spectroscopic follow-up clearly reveals extended Lyman-α\alpha in emission between two images of the central active galactic nucleus (AGN). We reconstruct the lensed quasar host galaxy in the source plane by applying a strong lens model to HST imaging, and resolve spatial scales as small as \sim200 parsecs. In the source plane we recover the host galaxy morphology to within a few hundred parsecs of the central AGN, and map the extended Lyman-α\alpha emission to its physical origin on one side of the host galaxy at radii \sim0.5-2 kpc from the central AGN. There are clear morphological differences between the Lyman-α\alpha and rest-frame ultraviolet stellar continuum emission from the quasar host galaxy. Furthermore, the relative velocity profiles of quasar Lyman-α\alpha, host galaxy Lyman-α\alpha, and metal lines in outflowing gas reveal differences in the absorbing material affecting the AGN and host galaxy. These data indicate the presence of patchy local intervening gas in front of the central quasar and its host galaxy. This interpretation is consistent with the central luminous quasar being obscured across a substantial fraction of its surrounding solid angle, resulting in strong anisotropy in the exposure of the host galaxy to ionizing radiation from the AGN. This work demonstrates the power of strong lensing-assisted studies to probe spatial scales that are currently inaccessible by other means.Comment: Accepted to ApJ Letters; 7 pages, 5 figure

    THz absorption spectrum of the CO2–H2O complex: Observation and assignment of intermolecular van der Waals vibrations

    Get PDF
    Terahertz absorption spectra have been recorded for the weakly bound CO2-H2O complex embedded in cryogenic neon matrices at 2.8 K. The three high-frequency van der Waals vibrational transitions associated with out-of-plane wagging, in-plane rocking, and torsional motion of the isotopic H2O subunit have been assigned and provide crucial observables for benchmark theoretical descriptions of this systems' flat intermolecular potential energy surface. A (semi)-empirical value for the zero-point energy of 273 ± 15 cm(-1) from the class of intermolecular van der Waals vibrations is proposed and the combination with high-level quantum chemical calculations provides a value of 726 ± 15 cm(-1) for the dissociation energy D0
    corecore