83 research outputs found

    Combined results of searches for the standard model Higgs boson in pp collisions at root s=7 TeV

    Get PDF
    Combined results are reported from searches for the standard model Higgs boson in proton-proton collisions at root s = 7 TeV in five Higgs boson decay modes: gamma gamma, bb, tau tau, WW, and ZZ. The explored Higgs boson mass range is 110-600 GeV. The analysed data correspond to an integrated luminosity of 4.6-4.8 fb(-1). The expected excluded mass range in the absence of the standard model Higgs boson is 118-543 GeV at 95% CL. The observed results exclude the standard model Higgs boson in the mass range 127-600 GeV at 95% CL, and in the mass range 129-525 GeV at 99% CL. An excess of events above the expected standard model background is observed at the low end of the explored mass range making the observed limits weaker than expected in the absence of a signal. The largest excess, with a local significance of 3.1 sigma, is observed for a Higgs boson mass hypothesis of 124 GeV. The global significance of observing an excess with a local significance >= 3.1 sigma anywhere in the search range 110-600 (110-145) GeV is estimated to be 1.5 sigma (2.1 sigma). More data are required to ascertain the origin of the observed excess. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved

    Measurement of the isolated prompt photon production cross section in pp collisions at √s=7 TeV

    Get PDF
    This is the pre-print version of the Published Article which can be accessed from the link below.The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy ETγ in pp collisions at √s=7  TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9  pb-1. Photons are required to have a pseudorapidity |ηγ|21  GeV, covering the kinematic region 0.006<xT<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations

    Study of high-p(T) charged particle suppression in PbPb compared to pp collisions at root s(NN)=2.76 TeV

    Get PDF
    The transverse momentum spectra of charged particles have been measured in pp and PbPb collisions at root s(NN) = 2.76 TeV by the CMS experiment at the LHC. In the transverse momentum range p(T) = 5-10 GeV/c, the charged particle yield in the most central PbPb collisions is suppressed by up to a factor of 7 compared to the pp yield scaled by the number of incoherent nucleon-nucleon collisions. At higher p(T), this suppression is significantly reduced, approaching roughly a factor of 2 for particles with p(T) in the range p(T) = 40-100 GeV/c

    stairs and fire

    Get PDF

    Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

    Get PDF
    A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

    Grid Connected Hybrid Solar and Diesel Generator Set: A Cost Optimization with HOMER

    No full text
    Extensive increases in electricity cost added to the numerous power outages encountered in developing countries has led to the deployment of hybrid energy supplies that mainly ensure continuity of power supply while attempting a reduction of electricity generation cost. This paper, specifically deals with the cost optimization of electricity generation from a grid connected hybrid solar and diesel generator. An electrical audit was first conducted on a selected building: the Electrical Block of Accra Technical University. The load estimate led to a total energy of 234 kWh for all electrical gadgets with the exception of the air-condition systems. The estimate was used to design the hybrid system with HOMER software that resulted in a total capacity of 115 kW and a levelized cost of electricity of 0.472 /kWhtakingintoconsiderationnopoweroutageintheyear.Furthermore,theproposedhybridsystemwasmadeofagridconnectedsolarsystemthatsuppliesthefullloadwiththeexceptionoftheairconditionsystemswhiletheNationalGridisusedtocovertherest.Insituationofpoweroutages,theGeneratorSettakesovertheNationalgridwhilethesolarisstillconnectedtotheGrid.Thismechanismwassimulatedandthecostofelectricityinabsenceofthegridwasestimatedat1.496/kWh taking into consideration no power outage in the year. Furthermore, the proposed hybrid system was made of a grid connected solar system that supplies the full load with the exception of the air-condition systems while the National Grid is used to cover the rest. In situation of power outages, the Generator Set takes over the National grid while the solar is still connected to the Grid. This mechanism was simulated and the cost of electricity in absence of the grid was estimated at 1.496 /kWh. A general cost of electricity taking into consideration 90% ON period of the grid against 10% Off period of the grid per year, was estimated to 0.574 $/kWh. Besides, the proposed system produced savings in emission of carbon dioxide, 26.42 kg/year, sulfur dioxide, 115 kg/year and Nitrogen oxides, 56 kg/year. Finally, the system yielded a very good payback period of 10.43 years with regard to a lifetime of 25 years
    corecore