27,501 research outputs found

    Can CPT Symmetry Be Tested With K^0 vs \bar{K}^0--> \pi^+\pi^-\pi^0 Decays?

    Full text link
    We show that the CP-violating effect in K^0 vs \bar K^0-->\pi^+\pi^-\pi^0 decays differs from that in K_{\rm L}-->\pi^+\pi^-, K_{\rm L}-->\pi^0\pi^0 or the semileptonic K_{\rm L} transitions, if there exists CPT violation in K^0-\bar{K}^0 mixing. A delicate measurement of this difference in the KTeV experiment and at the \phi factory will provide a new test of CPT symmetry in the neutral kaon system.Comment: RevTex 6 pages. Phys. Rev. D (in printing

    Energy Loss and Flavor Dynamics from Single Particle Measurements in PHENIX

    Full text link
    The transverse momentum spectra, yields, and ratios of charged pions, protons, and antiprotons have been studied up to 5 GeV/c in pTp_T in 5 different centrality classes in Au+Au collisions at sNN\sqrt{s_{NN}} = 200 GeV. These results are compared and contrasted with the observables calculated in recombination models of hadronization. They are also used to examine the color charge dependence of parton energy loss in the medium.Comment: 4 pages, 6 figures, to appear in the Proceedings of Quark Matter 200

    Aluminum alloys with improved strength

    Get PDF
    Mechanical strength and stress corrosion of new BAR and 7050 alloys that include Zn instead of Cr have been studied and compared with those of 7075 aluminum alloy. Added mechanical strength of new alloys is attributed to finer grain size of 5 to 8 micrometers, however, susceptibility to stress corrosion attack is increased

    Euler Integration of Gaussian Random Fields and Persistent Homology

    Full text link
    In this paper we extend the notion of the Euler characteristic to persistent homology and give the relationship between the Euler integral of a function and the Euler characteristic of the function's persistent homology. We then proceed to compute the expected Euler integral of a Gaussian random field using the Gaussian kinematic formula and obtain a simple closed form expression. This results in the first explicitly computable mean of a quantitative descriptor for the persistent homology of a Gaussian random field.Comment: 21 pages, 1 figur

    Avoidance of stress corrosion susceptibility in high strength aluminum alloys by control of grain boundary and matrix microstructure

    Get PDF
    The relation of microstructure to the mechanical strength and stress corrosion resistance of highest strength and overaged tempers of BAR and 7050 aluminum alloys was investigated. Comparison is made with previously studied 7075 aluminum alloy. Optical microscopy, transmission electron microscopy, and differential scanning calorimetry were used to characterize the grain morphology, matrix microstructure, and grain boundary microstructure of these tempers. Grain boundary interparticle spacing was significant to stress corrosion crack propagation for all three alloys; increasing interparticle spacing led to increased resistance to crack propagation. In addition, the fire grain size in Bar and 7050 appears to enhance crack propagation. The highest strength temper of 7050 has a comparatively high resistance to crack initiation. Overall stress corrosion behavior is dependent on environment pH, and evaluation over a range of pH is recommended

    Rossby waves and α\alpha-effect

    Full text link
    Rossby waves drifting in the azimuthal direction are a common feature at the onset of thermal convective instability in a rapidly rotating spherical shell. They can also result from the destabilization of a Stewartson shear layer produced by differential rotation as expected in the liquid sodium experiment (DTS) working in Grenoble, France. A usual way to explain why Rossby waves can participate to the dynamo process goes back to Busse (1975). In his picture, the flow geometry is a cylindrical array of parallel rolls aligned with the rotation axis. The axial flow component (the component parallel to the rotation axis) is (i) maximum in the middle of each roll and changes its sign from one roll to the next. It is produced by the Ekman pumping at the fluid containing shell boundary. The corresponding dynamo mechanism can be explained in terms of an α\alpha-tensor with non-zero coefficients on the diagonal. In rapidly rotating objects like the Earth's core (or in a fast rotating experiment), Rossby waves occur in the limit of small Ekman number (≈10−15\approx 10^{-15}). In that case, the main source of the axial flow component is not the Ekman pumping but rather the ``geometrical slope effect'' due to the spherical shape of the fluid containing shell. This implies that the axial flow component is (ii) maximum at the borders of the rolls and not at the centers. If assumed to be stationary, such rolls would lead to zero coefficients on the diagonal of the α\alpha-tensor, making the dynamo probably less efficient if possible at all. Actually, the rolls are drifting as a wave, and we show that this drift implies non--zero coefficients on the diagonal of the α\alpha-tensor. These new coefficients are in essence very different from the ones obtained in case (i) and cannot be interpreted in terms of the heuristic picture of Busse (1975)

    Interhemispheric comparison of atmospheric circulation features as evaluated from Nimbus satellite data. A comparison of the structure and flow characteristics of the upper troposphere and stratosphere of the Northern and Southern Hemispheres

    Get PDF
    The general circulations of the Northern and Southern Hemispheres are compared with regard to the upper troposphere and stratosphere, using atmospheric structure obtained from multi-channel radiance data from the satellite infrared spectrometer instrument aboard the Nimbus 3 spacecraft. The inter-hemispheric comparisons are based on two months of data (one summer month and one winter month) in each hemisphere. Topics studied include: (1) mean meridional circulation in the Southern Hemisphere stratosphere; (2) magnitude and distribution of tropospheric eddy heat flux; (3) relative importance of standing and transient eddies in the two hemispheres; (4) magnitudes of energy cycle components; and (5) the relation of vortex structure to the breakdown climatology of the Antarctic stratospheric polar vortex

    Nondispersive X-ray emission analysis for geochemical exploration

    Get PDF
    Nondispersive X-ray emission technique uses lightweight, and rugged X-ray fluorescence units. The X-ray pulse-height spectra is excited by radioactive isotope sources. The technique is applicable for quantitative and qualitative analyses on complex chemical systems, and satisfies the goals for a lunar geochemical exploration device

    The Legal, Ethical, and Social Implications of the Reasonable Woman Standard in Sexual Harassment Cases

    Get PDF
    In this Article, Professors Adler and Peirce examine the development and implications of the reasonable woman standard that is gaining increasing acceptance as the appropriate gauge for measuring the offensiveness of the conduct at issue in sexual harassment cases. The authors begin by reviewing the origins of sexual harassment law under Title VII of the Civil Rights Act of 1964, paying particular attention to the history of hostile environment causes of action. Professors Adler and Peirce then discuss how and why the reasonable woman standard evolved as an alternative to the conventional reasonable man and reasonable person standards that had been the usual measures of culpable conduct in sexual harassment cases, and how courts have applied the reasonable woman standard in cases involving a wide range of allegedly harassing behaviors. The authors conclude by discussing a variety of important concerns raised by the implementation of the reasonable woman standard, including the fundamental question of whether it is fair to hold men to a standard of conduct that, because they are men, they may be unable to understand or appreciate fully
    • …
    corecore