1,797 research outputs found

    Low-lying resonances of Be9Lambda : Faddeev calculation with Pade-approximants

    Full text link
    Configuration space Faddeev equations are applied to describe the Be9Lambda low-lying resonances of the ground band in the alpha+alpha+Lambda cluster model. The method of analytical continuation in coupling constant is used.Comment: 4 pages, 3 Postscript figures, Talk at the 18th International IUPAP Conference on Few-Body Problems in Physics, Aug. 21-26, 2006, Santos, Brazi

    Discrimination of SUSY breaking models using single-photon processes at future e+e- linear colliders

    Full text link
    We examine the single-photon processes in the frame work of supersymmetric models at future e+e- linear colliders. According to the recent experimental achievement, the optimistic polarization degrees for both electron and positron beams are taken into account to enhance the signal-to-noise ratio revealing the observable difference between supersymmetry breaking models. The minimal supergravity model and the minimal SU(5) grand unified model in gaugino mediation have been examined as examples. We see that after several years of accummulating data, the difference of the number of single-photon events between the two models received from the collider would be in excess of three times the statistical error, providing us the possibility to probe which model would be realized in nature. The result is well suitable for the future running of the International Linear Collider.Comment: 14 pages, 4 figures, version to be published in Mod. Phys. Lett.

    Numerical simulation of 3-D flow around sounding rocket in the lower thermosphere

    Get PDF
    International audienceNumerical simulations using the Direct Simulation Monte Carlo (DSMC) method are known to be useful for analyses of aerodynamic effects on in-situ rocket measurements in the lower thermosphere, but the DSMC analysis of a spin modulation caused by an asymmetric flow around the rocket spin axis has been restricted to the two-dimensional and axially symmetric simulations in actual sounding rocket experiments. This study provides a quantitative analysis of the spin modulation using a three-dimensional (3-D) simulation of the asymmetric flow with the DSMC method. Clear spin modulations in the lower thermospheric N2 density measurement by a rocket-borne instrument are simulated using the rocket attitude and velocity, the simplified payload structure, and the approximated atmospheric conditions. Comparison between the observed and simulated spin modulations show a very good agreement within 5% at around 100km. The results of the simulation are used to correct the spin modulations and derive the absolute densities in the background atmosphere

    Cluster models of Lambda-Lambda-6He and Lambda-9Be hypernuclei

    Full text link
    Configuration space Faddeev calculations are performed for the binding energy of Lambda-Lambda-6He and Lambda-9Be bound states, here considered as alpha-Lambda-Lambda and alpha-alpha-Lambda clusters respectively, in order to study the dependence of the calculated binding energy on the alpha-Lambda potential input. For Lambda-Lambda-6He, using realistic interactions, the uncertainty in extracting the Lambda-Lambda S=L=0 interaction strength does not exceed 0.1 MeV, which is a fraction of the order of magnitude derived for other theoretical uncertainties. For Lambda-9Be, the dependence of the calculated binding energy on the alpha-Lambda potential is considerably larger, of order 1 MeV. Our results for Lambda-9Be suggest that the odd-state alpha-Lambda interaction is substantially reduced with respect to the even-state component.Comment: 16 pages, including 4 figures, typos corrected, slightly revised, accepted to Nuclear Physics

    Josephson π\pi-state in superconductor-Luttinger liquid hybrid systems

    Full text link
    Josephson current through a Luttinger liquid (LL) under a magnetic field is theoretically studied. We derive an analytical expression of Josephson current for clean interfaces, by using quasiclassical Green's function and functional bosonization procedure. We show that critical currents can be renormalized by electron-electron interactions at perfect transparency when LL is adiabatically connected with superconductors. We also find that a generation of π\pi-state, due to spin-dependent energy shift in Andreev bound states (ABS), is prohibited even at zero temperature when the strength of repulsive interactions reaches some critical value. The suppression of π\pi-state is caused by the low energy fluctuations propagating in LL, and making the Zeeman splitting in ABS blurred.Comment: 5 pages, 4figure

    Detection and Localization of Periodontopathic Bacteria in Abdominal Aortic Aneurysms

    Get PDF
    AbstractObjectivesWe examined a possible link between periodontal disease and abdominal aortic aneurysm (AAA) by studying resected aneurysmal specimens from AAA patients for the presence of periodontitopathic bacteria.DesignProspective case control study.Material and methodsThirty-two AAA patients were enrolled in the study. Periodontitis was classified according to the probing depth of preriodontal pocket. Thirty-two aneurysmal walls, 16 mural thrombi, 5 atherosclerotic occlusive aorta and 5 control arterial tissue, were examined for 7 periodontal bacteria using polymerase chain reaction (PCR) method. The localization of the bacteria in the aneurysmal/atherosclerotic wall was determined by thromboendarterectomy.ResultsAll patients had periodontal disease, and most cases were severe. PCR examination of the aneurysmal specimens showed that 86% were positive for periodontal bacterial DNA. No bacteria were detected in the control specimens. The bacteria were found in both the intimal/medial layer and the adventitial layer of the aneurysmal wall but only in intimal/medial layer of the atherosclerotic occlusive aorta.ConclusionPeriodontopathic bacteria were present in a high percentage of specimens of diseased arteries from AAA patients and were found throughout the whole aneurysmal wall. These bacteria may play a role in the development of AAAs and/or contribute to weakening the aneurysmal wall

    Efficient, XOR-Based, Ideal (t,n)− threshold Schemes

    Get PDF
    We propose a new, lightweight (t; n) threshold secret shar- ing scheme that can be implemented using only XOR operations. Our scheme is based on an idea extracted from a patent application by Hewlett Packard that utilises error correction codes. Our scheme im- proves on the patent by requiring fewer randomly generated bits and by reducing the size of shares given to each player, thereby making the scheme ideal. We provide a security proof and e ciency analysis. We compare our scheme to existing schemes in the literature and show that our scheme is more e cient than other schemes, especially when t is large
    • …
    corecore