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71.
The search for MSSM Higgs bosons will be an important goal at the LHC. We analyze the search reach of the CMS experiment for the heavy neutral MSSM Higgs bosons with an integrated luminosity of 30 or 60 fb-1. This is done by combining the latest results for the CMS experimental sensitivities based on full simulation studies with state-of-the-art theoretical predictions of the MSSM Higgs-boson properties. The results are interpreted in MSSM benchmark scenarios in terms of the parameters tan β and the Higgs-boson mass scale, MA. We study the dependence of the 5σ discovery contours in the MA–tan β plane on variations of the other supersymmetric parameters. The largest effects arise from a change in the higgsino mass parameter μ, which enters both via higher-order radiative corrections and via the kinematics of Higgs decays into supersymmetric particles. While the variation of μ can shift the prospective discovery reach (and correspondingly the ”LHC wedge” region) by about Δtan β=10, we find that the discovery reach is rather stable with respect to the impact of other supersymmetric parameters. Within the discovery region we analyze the accuracy with which the masses of the heavy neutral Higgs bosons can be determined. We find that an accuracy of 1–4% should be achievable, which could make it possible in favorable regions of the MSSM parameter space to experimentally resolve the signals of the two heavy MSSM Higgs bosons at the LHC.  相似文献   
72.
The production mechanisms and decay modes of the heavy neutral and charged Higgs bosons in the Minimal Supersymmetric Standard Model are investigated at future e + e ? colliders in the TeV energy regime. We generate supersymmetric particle spectra by requiring the MSSM Higgs potential to produce correct radiative electroweak symmetry breaking, and we assume a common scalar mass m0, gaugino mass m1/2 and trilinear coupling A, as well as gauge and Yukawa coupling unification at the Grand Unification scale. Particular emphasis is put on the low tan β solution in this scenario where decays of the Higgs bosons to Standard Model particles compete with decays to supersymmetric charginos/neutralinos as well as sfermions. In the high tan β case, the supersymmetric spectrum is either too heavy or the supersymmetric decay modes are suppressed, since the Higgs bosons decay almost exclusively into b and τ pairs. The main production mechanisms for the heavy Higgs particles are the associated AH production and H +H? pair production with cross sections of the order of a few fb.  相似文献   
73.
This paper is devoted to an (n+4)-dimensional unification of NGT (nonsymmetric gravitation theory) and Yang-Mills theory in a Jordan-Thiry manner. We find interference effects between gravitational and Yang-Mills fields which appear to be due to the skew-symmetric part of the metric on the (n+4)-dimensional manifold (nonsymmetrically metrized principal fiber bundle). Our unification, called the nonsymmetric-non-Abelian Jordan-Thiry theory, becomes classical if the skew-symmetric part of the metric is zero. We find the Yang-Mills field Lagrangian up to the second order of approximation inh =g . We also deal with the Lagrangian for the scalar field (connected to the gravitational constant). We consider the spin content of the theory and a relationship between the cosmological constant and the coupling constant between the skewon field and the gauge field in the first order of approximation. We show how to derive a dielectric model of a confinement from interference effects in these theories. We underline some similarities between the nonsymmetric Jordan-Thiry Lagrangian in the flat space limit and the soliton bag model Lagrangian.  相似文献   
74.
75.
Higgs particles can be radiated off heavy top quarks which will be produced copiously in high energye + e ? colliders. This process can be used to measure the Higgs-top quark coupling. We present the cross section for the production of Higgs bosons in the Standard Model. In addition we have studied the production of neutral and charged Higgs particles in association with heavy fermions in the Minimal Supersymmetric Standard Model.  相似文献   
76.
Solid-state transitions in crystalline tetracene have been investigated by Raman spectroscopy and by anisotropy of the effect of a magnetic field on its prompt fluorescence. Discontinuous changes in the temperature dependence of Raman lattice modes and new phonon lines occur near 182 and 144 K, signifying the occurrence of two phase transitions. The magnetic anisotropy effect shows a gradual change with temperature, suggesting the transition at 182 K is preceded by a continuous rotation of the intermolecular plane.  相似文献   
77.
13C NMR spectra of 11 di-, tri- and tetra-tert-butyl-substituted cyclopentadienones are discussed with respect to charge distribution and substituent effects. The chemical shifts of the unsubstituted cyclopentadienone, calculated from substituent increments, are in good agreement with published CNDO calculations and can be rationalized by the inductive effect of the carbonyl group. In addition, the ESR signals shown by some of the cyclopentadienones are described, and possible reasons for their appearance are discussed.  相似文献   
78.
In this paper a catalogue of all maximal nonhamiltonian graphs of orders up to 10 is provided. Special attention is paid to maximal nonhamiltonian graphs with non-positive scattering number since all remaining ones (with scattering number 1) are fully characterized and counted by the third author. We also give a sketch of the method used to produce the catalogue.  相似文献   
79.
The 13C-chemical shifts of methyl substituted ureas, thioureas and related compounds are reported and discussed. π-Electron densities, as obtained by simple HMO calculations, do not reproduce the 13C-chemical shift trend. A correlation has been found for the carbonyl and thiocarbonyl resonances which has been discussed as being mainly influenced by the mean excitation energy in the paramagnetic screening term.  相似文献   
80.
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