1,189 research outputs found

    Production of Black Holes in TeV-Scale Gravity

    Get PDF
    Copious production of microscopic black holes is one of the least model-dependent predictions of TeV-scale gravity scenarios. We review the arguments behind this assertion and discuss opportunities to track the striking associated signatures in the near future. These include searches at neutrino telescopes, such as AMANDA and RICE, at cosmic ray air shower facilities, such as the Pierre Auger Observatory, and at colliders, such as the Large Hadron Collider.Comment: 8 pages, 10 figures, fortschritte.sty (included); talk presented at the 35th International Symposium Ahrenshoop on the Theory of Elementary Particles, Aug. 26-30, 2002, Berlin-Schmoeckwitz, German

    Zooming-in on Instantons at HERA

    Get PDF
    In view of the intriguing, preliminary search results for instanton-induced events at HERA from the H1 collaboration, some important remaining theoretical issues are discussed. Notably, the question is addressed, to which extent the H1 analysis may be directly compared to our original predictions from instanton-perturbation theory, since certain fiducial cuts are lacking in the H1 data. Various theoretical uncertainties are evaluated and their impact on the observed excess is discussed. An improved understanding of the experimental findings along with an encouraging over-all agreement with our original predictions seems to emerge.Comment: 13 pages, 12 figure

    QCDINS 2.0 - A Monte Carlo generator for instanton-induced processes in deep-inelastic scattering

    Get PDF
    We describe a Monte Carlo event generator for the simulation of QCD-instanton induced processes in deep-inelastic scattering (HERA). The QCDINS package is designed as an ``add-on'' hard process generator interfaced to the general hadronic event simulation package HERWIG. It incorporates the theoretically predicted production rate for instanton-induced events as well as the essential characteristics that have been derived theoretically for the partonic final state of instanton-induced processes: notably, the flavour democratic and isotropic production of the partonic final state, energy weight factors different for gluons and quarks, and a high average multiplicity O(10) of produced partons with a Poisson distribution of the gluon multiplicity. While the subsequent perturbative evolution of the generated partons is always handled by the HERWIG package, the final hadronization step may optionally be performed also by means of the general hadronic event simulation package JETSET.Comment: 51 pages, 3 figure

    Phenomenology of Multi-W Processes in Cosmic Rays

    Full text link
    We report on a study of the potential of various cosmic ray physics experiments to search for Standard Model processes involving the nonperturbative production of O(30) weak gauge bosons. Whereas present and near-future experiments are insensitive to proton-induced processes, neutrino-induced processes give rise to promising signatures and rates in AMANDA, DUMAND, MACRO and NESTOR provided that a cosmic neutrino flux exists at levels suggested by recent models of active galactic nuclei. The Fly's Eye currently constrains the largest region of parameter space characterizing multi-W phenomena.Comment: (Invited talk presented by A. Ringwald at 17th Johns Hopkins Workshop on Current Problems in Particle Theory, Particles and the Universe, July 30-August 1, 1993, Budapest, Hungary), 16 pages (LaTeX) + 10 uuencoded PostScript figures, CERN-TH.7005/93, UCLA/93/TEP/3
    • …