55 research outputs found

    Death due to ingestion of nicotine-containing solution: Case report and review of the literature

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    Nicotine, a lipid-soluble alkaloid obtained from the dried leaves of Nicotiana, is most frequently encountered in tobacco products for smoking, chewing or sniffing as well as in a limited number of pesticides. Though nicotine is one of the most toxic drugs of abuse, it has rarely led to fatalities. Sudden death can be caused by cardiovascular arrest, respiratory muscle paralysis and/or central respiratory failure. A 42-year-old man was found dead by his wife. He was lying on the floor, next to a box containing many empty bottles of beer and vodka. Some labeled chemical bottles found at the scene contained various substances, including nicotine and brucine. Gross examination of the organs at autopsy revealed no specific findings. The toxicological examination failed to disclose any lethal toxic agents other than a high concentration of nicotine and its primary metabolite cotinine in femoral venous blood (2.2 μg/mL). Blood alcohol was determined to be 2.1 g/L in femoral venous blood. Only a paucity of fatal cases of nicotine poisoning has been reported in the literature so far. © 2009 Elsevier Ireland Ltd. All rights reserved

    Testing nonperturbative techniques in the scalar sector of the standard model

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    We discuss the current picture of the standard model's scalar sector at strong coupling. We compare the pattern observed in the scalar sector in perturbation theory up to two-loop with the nonperturbative solution obtained by a next-to-leading order 1/N expansion. In particular, we analyze two resonant Higgs scattering processes, ff -> H -> f'f' and ff -> H -> ZZ, WW. We describe the ingredients of the nonperturbative calculation, such as the tachyonic regularization, the higher order 1/N intermediate renormalization, and the numerical methods for evaluating the graphs. We discuss briefly the perspectives and usefulness of extending these nonperturbative methods to other theories

    Matching conditions and Higgs mass upper bounds revisited

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    Matching conditions relate couplings to particle masses. We discuss the importance of one-loop matching conditions in Higgs and top-quark sector as well as the choice of the matching scale. We argue for matching scales μ0,tmt\mu_{0,t} \simeq m_t and μ0,Hmax[mt,MH]\mu_{0,H} \simeq max[ m_t, M_H ]. Using these results, the two-loop Higgs mass upper bounds are reanalyzed. Previous results for Λ\Lambda\approx few TeV are found to be too stringent. For Λ=1019\Lambda=10^{19} GeV we find MH<180±4±5M_H < 180 \pm 4\pm 5 GeV, the first error indicating the theoretical uncertainty, the second error reflecting the experimental uncertainty due to mt=175±6m_t=175\pm6 GeV.Comment: 20 pages, 6 figures; uses epsf and rotate macro

    Ruling Out a Strongly-Interacting Standard Higgs Model

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    Previous work has suggested that perturbation theory is unreliable for Higgs- and Goldstone-boson scattering, at energies above the Higgs mass, for relatively small values of the Higgs quartic coupling λ(μ)\lambda(\mu). By performing a summation of nonlogarithmic terms, we show that perturbation theory is in fact reliable up to relatively large coupling. This eliminates the possibility of a strongly-interacting standard Higgs model at energies above the Higgs mass, complementing earlier studies which excluded strong interactions at energies near the Higgs mass. The summation can be formulated in terms of an appropriate scale in the running coupling, μ=s/es/2.7\mu=\sqrt{s}/e\approx\sqrt{s}/2.7, so it can easily be incorporated in renormalization-group improved tree-level amplitudes as well as higher-order calculations.Comment: 29 pages, 6 figures. The complete paper including figures is also available via WWW at http://www.physik.tu-muenchen.de/tumphy/d/T30d/PAPERS/TUM-HEP-236-96.ps.g

    Heavy-Higgs Lifetime at Two Loops

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    The Standard-Model Higgs boson with mass MH>>2MZ M_H >> 2M_Z decays almost exclusively to pairs of WW and ZZ bosons. We calculate the dominant two-loop corrections of O(GF2MH4) O( G_F^2 M_H^4 ) to the partial widths of these decays. In the on-mass-shell renormalization scheme, the correction factor is found to be 1+14.6 1 + 14.6 % (M_H/TeV)^2 + 16.9 % (M_H/TeV)^4 , where the second term is the one-loop correction. We give full analytic results for all divergent two-loop Feynman diagrams. A subset of finite two-loop vertex diagrams is computed to high precision using numerical techniques. We find agreement with a previous numerical analysis. The above correction factor is also in line with a recent lattice calculation.Comment: 26 pages, 6 postscript figures. The complete paper including figures is also available via WWW at http://www.physik.tu-muenchen.de/tumphy/d/T30d/PAPERS/TUM-HEP-247-96.ps.g

    The Higgs resonance in vector boson scattering

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    A heavy Higgs resonance is described in a representation-independent way which is valid for the whole energy range of 2 -> 2 scattering processes, including the asymptotic behavior at low and high energies. The low-energy theorems which follow from to the custodial SU_2 symmetry of the Higgs sector restrict the possible parameterizations of the lineshape that are consistent in perturbation theory. Matching conditions are specified which are necessary and sufficient to relate the parameters arising in different expansions. The construction is performed explicitly up to next-to-leading order.Comment: 25 pages, revtex, uses epsf, amssym

    The Goldstone boson equivalence theorem with fermions

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    The calculation of the leading electroweak corrections to physical transition matrix elements in powers of MH2/v2M_H^2/v^2 can be greatly simplified in the limit MH2MW2,MZ2M_H^2\gg M_W^2,\, M_Z^2 through the use of the Goldstone boson equivalence theorem. This theorem allows the vector bosons W±W^\pm and ZZ to be replaced by the associated scalar Goldstone bosons w±w^\pm, zz which appear in the symmetry breaking sector of the Standard Model in the limit of vanishing gauge couplings. In the present paper, we extend the equivalence theorem systematically to include the Yukawa interactions between the fermions and the Higgs and Goldstone bosons of the Standard Model. The corresponding Lagrangian LEQT{\cal L}_{EQT} is given, and is formally renormalized to all orders. The renormalization conditions are formulated both to make connection with physical observables and to satisfy the requirements underlying the equivalence theorem. As an application of this framework, we calculate the dominant radiative corrections to fermionic Higgs decays at one loop including the virtual effects of a heavy top quark. We apply the result to the decays HttˉH\rightarrow t\bar{t} and HbbˉH\rightarrow b\bar{b}, and find that the equivalence theorem results including fermions are quite accurate numerically for Higgs-boson masses MH>400(350)M_H> 400\,(350) GeV, respectively, even for mt=175m_t=175 GeV.Comment: 32 pages, uses LaTeX2e, epsf and rotate, 7 figures included as separate uuencoded packed file. A complete PostScript version can also be obtained from http://www.physik.tu-muenchen.de/tumphy/d/T30d/PAPERS/TUM-HEP-227-95.ps.g

    Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF

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    The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described

    The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

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    Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figuresMajor update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figuresThe preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess

    The DUNE Far Detector Interim Design Report, Volume 3: Dual-Phase Module

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    The DUNE IDR describes the proposed physics program and technical designs of the DUNE far detector modules in preparation for the full TDR to be published in 2019. It is intended as an intermediate milestone on the path to a full TDR, justifying the technical choices that flow down from the high-level physics goals through requirements at all levels of the Project. These design choices will enable the DUNE experiment to make the ground-breaking discoveries that will help to answer fundamental physics questions. Volume 3 describes the dual-phase module's subsystems, the technical coordination required for its design, construction, installation, and integration, and its organizational structure
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