251,567 research outputs found

    Discovery of Newly Formed Broad Absorption Lines in a Radio-Loud Quasar

    Get PDF
    We report a serendipitous discovery of broad absorption lines that were newly formed in the spectrum of the high-redshift, luminous radio-loud quasar TEX 1726 + 344, in a time interval of only 12 years. This is the first quasar showing a transition from narrow absorption lines to broad absorption lines. It also becomes one of the few radio-loud broad absorption line quasars. The gas cloud responsible for these broad absorption lines is derived to have parameters coinciding with those of the remnant of a tidally disrupted star.Comment: 6 pages, 1 figure, accepted for publication as a Letter in Mon. Not. R. Astron. So

    Comment on ``Signal of Quark Deconfinement in the Timing Structure of Pulsar Spin-Down''

    Get PDF
    This is a comment on a paper by Glendenning, Pei, and Weber (Phys. Rev. Lett., 79, 1603, 1997), where the authors gave an incorrect estimate of the event rate and neglected the important gravitational energy release. Previous work on the same subject is reviewed, and a new suggestion is made to link quark-hadron phase transitions with soft gamma-ray repeaters.Comment: 4 pages; to appear in Phys. Rev. Let

    The Steady-State Response of a Class of Dynamical Systems to Stochastic Excitation

    Get PDF
    In this paper a class of coupled nonlinear dynamical systems subjected to stochastic excitation is considered. It is shown how the exact steady-state probability density function for this class of systems can be constructed. The result is then applied to some classical oscillator problems

    Evaluation of commercial GaN HEMTs for pulsed power applications

    Get PDF
    A non-conformally invariant coupling between the inflaton and the photon in the minimal Lorentz-violating standard model extension is analyzed. For specific forms of the Lorentz-violating background tensor, the strong-coupling and back-reaction problems of magnetogenesis in de Sitter inflation with scale 1016GeV{\sim }10^{16}\,\hbox {GeV} are evaded, the electromagnetic-induced primordial spectra of (Gaussian and non-Gaussian) scalar and tensor curvature perturbations are compatible with cosmic microwave background observations, and the inflation-produced magnetic field directly accounts for cosmic magnetic fields

    Pulsed operation and performance of commercial GaN HEMTs

    Get PDF

    Evaluation of commercial GaN HEMTs for pulsed power applications

    Get PDF
    corecore