26,022 research outputs found

    A General MSSM Parameter Scan

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    The excluded tan(beta) range and Higgs boson mass regions in the framework of the Minimal Supersymmetric extension of the Standard Model (MSSM) depend on several parameters. The Higgs boson masses, cross-sections and branching fractions have been determined including two-loop diagrammatic calculations. The limits obtained with a more general scan over the parameter space of the MSSM are compared with those in the so-called benchmark scenario. The combination of the searches for Higgs particles in the 1999 data collected by the DELPHI collaboration at center-of-mass energies between 191.6 and 201.7 GeV allows stringent limits to be set in combination with previous DELPHI results. In addition, an interpretation in the framework of the general MSSM scan of the 2000 LEP data at the hightest energies between 201.7 and 209.0 GeV is given. We show that the current data for the HZ and hA production can be comfortably accommodated in the MSSM.Comment: 3 pages, 3 figure

    Orthogonal subsets of classical root systems and coadjoint orbits of unipotent groups

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    Let Ί\Phi be a classical root system and kk be a field of sufficiently large characteristic. Let GG be the classical group over kk with the root system Ί\Phi, UU be its maximal unipotent subgroup and u\mathfrak{u} be the Lie algebra of UU. Let DD be an orthogonal subset of Ί\Phi and Ω\Omega be a coadjoint orbit of UU associated with DD. We construct a polarization of u\mathfrak{u} at the canonical form on Ω\Omega. We also find the dimension of Ω\Omega in terms of the Weyl group of Ί\Phi. As a corollary, we determine all possible dimensions of irreducible complex represenations of the group UU for the case of finite field kk.Comment: 11 page

    Comparison of Higgs Boson Mass and Width Determination of the LHC and a Linear Collider

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    Two important properties of a Higgs boson are its mass and width. They may distinguish the Standard Model (SM) Higgs boson from Higgs bosons of extended models. We show results from a direct mass and width reconstruction for a Higgs boson mass range from 120 to 340 GeV. The mass and width have been reconstructed from the H --> ZZstar --> mu+mu-mu+mu- reaction in an LHC simulation of the CMS detector. The determined mass accuracy has been compared with that obtained from studies for a linear collider (LC). The mass precision from the latter studies is derived by scaling previous LC simulation results according to the expected event rates. For the Higgs boson width we compare a direct determination with indirect methods and find good complementarity.Comment: 4 pages, 4 figure

    “The Right to the City” An Ecosystemic Approach to Better Cities, Better Life

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    Urbanism is a focus on cities and urban areas, their geography, economies, politics, social characteristics, as well as the effects on, and caused by, the built environment; it is linked to various aspects of quality of life: education, culture, justice, labour, environment, health, safety, housing, leisure, transport, consumption. This year, the United Nations proposed the following questions for the citizens of the world: What is the best thing about your city? What's the worst thing about your city? What do you want the authorities to do about it? What can you do about it? It is a clear attempt to foster civic participation and personal engagement, but to make things happen it is necessary to create active socio-cultural niches at many societal levels.Urbanism; politics; education; culture; justice

    Hard parton damping in hot QCD

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    The gluon and quark collisional widths in hot QCD plasmas are discussed with emphasis on temperatures near Tc, where the coupling is large. Considering the effect on the entropy, which is known from lattice calculations, it is argued that the width of the partons, which in the perturbative limit is given by gamma ~ g^2 ln(1/g) T, should be sizeable at intermediate temperatures but has to be small close to Tc. This behavior implies a substantial reduction of the radiative energy loss of jets near Tc.Comment: invitetd talk given at 'Hot Quarks 04', July 18-24 2004, Taos Valley, NM, US
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