49 research outputs found

    Bound states of scalar particles in the presence of a short range potential

    Full text link
    We analyze the behavior of the energy spectrum of the Klein-Gordon equation in the presence of a truncated hyperbolic tangent potential. From our analysis we obtain that, for some values of the potential there is embedding of the bound states into the negative energy continuum, showing that, in opposition to the general belief, relativistic scalar particles in one-dimensional short range potentials can exhibit resonant behavior and not only the Schiff-Snyder effect.Comment: To appear in Modern Physics Letters

    The question concerning human rights and human rightlessness: disposability and struggle in the Bhopal gas disaster

    Get PDF
    In the midst of concerns about diminishing political support for human rights, individuals and groups across the globe continue to invoke them in their diverse struggles against oppression and injustice. Yet both those concerned with the future of human rights and those who champion rights activism as essential to resistance, assume that human rights – as law, discourse and practices of rights claiming – can ameliorate rightlessness. In questioning this assumption, this article seeks also to reconceptualise rightlessness by engaging with contemporary discussions of disposability and social abandonment in an attempt to be attentive to forms of rightlessness co-emergent with the operations of global capital. Developing a heuristic analytics of rightlessness, it evaluates the relatively recent attempts to mobilise human rights as a frame for analysis and action in the campaigns for justice following the 3 December 1984 gas leak from Union Carbide Corporation’s (UCC) pesticide manufacturing plant in Bhopal, India. Informed by the complex effects of human rights in the amelioration of rightlessness, the article calls for reconstituting human rights as an optics of rightlessness

    Optics and Quantum Electronics

    Get PDF
    Contains table of contents on Section 3 and reports on nineteen research projects.Defense Advanced Research Projects Agency Grant F49620-96-0126Joint Services Electronics Program Grant DAAH04-95-1-0038National Science Foundation Grant ECS 94-23737U.S. Air Force - Office of Scientific Research Contract F49620-95-1-0221U.S. Navy - Office of Naval Research Grant N00014-95-1-0715Defense Advanced Research Projects Agency/National Center for Integrated Photonics TechnologyMultidisciplinary Research InitiativeU.S. Air Force - Office of Scientific ResearchNational Science Foundation/MRSECU.S. Navy - Office of Naval Research (MFEL) Contract N00014-91-J-1956National Institutes of Health Grant R01-EY11289U.S. Navy - Office of Naval Research (MFEL) Contract N00014-94-0717Defense Advanced Research Projects Agency Contract N66001-96-C-863

    Whistleblowing: Incentives and Situational Determinants

    Full text link
    Law makers increasingly try to capitalize on individuals having acquired knowledge of corporate crimes or other misconduct by inducing them to blow the whistle. In a laboratory experiment we measure the effectiveness of incentives on the willingness to report such misconduct to a sanctioning authority. We find that fines for non-reporting insiders, rewards and even simple commands increase the probability of whistleblowing. We find the strongest effect for fines. Situational determinants also influence the willingness to blow the whistle: Insiders who are negatively affected by the misconduct are more likely to blow the whistle than non-affected or profiting insiders. Those (negatively affected) victims are also sensitive to the misconduct's impact on the authority sanctioning the misconduct (public authority or employer): Whistleblowing is more likely if the enforcement authority is negatively affected compared to positively or not affected.November 201

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

    Get PDF
    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≀0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

    Ultralight vector dark matter search using data from the KAGRA O3GK run

    Get PDF
    Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

    Get PDF
    corecore