26 research outputs found

    Search for neutral resonances decaying into a Z boson and a pair of b jets or τ leptons

    Get PDF
    A search is performed for a new resonance decaying into a lighter resonance and a Z boson. Two channels are studied, targeting the decay of the lighter resonance into either a pair of oppositely charged τ leptons or a bb‾ pair. The Z boson is identified via its decays to electrons or muons. The search exploits data collected by the CMS experiment at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.8 fb −1 . No significant deviations are observed from the standard model expectation and limits are set on production cross sections and parameters of two-Higgs-doublet models

    Search for Narrow Resonances Decaying to Dijets in Proton-Proton Collisions at root s=13 TeV

    Get PDF
    Peer reviewe

    Search for R-parity violating decays of a top squark in proton–proton collisions at √s=8 TeV

    Get PDF
    The results of a search for a supersymmetric partner of the top quark (top squark), pair-produced in proton–proton collisions at View the MathML sources=8 TeV, are presented. The search, which focuses on R-parity violating, chargino-mediated decays of the top squark, is performed in final states with low missing transverse momentum, two oppositely charged electrons or muons, and at least five jets. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 fb−1 collected with the CMS detector at the LHC in 2012. The data are found to be in agreement with the standard model expectation, and upper limits are placed on the top squark pair production cross section at 95% confidence level. Assuming a 100% branching fraction for the top squark decay chain, View the MathML sourcet˜→tχ˜1±,χ˜1±→ℓ±+jj, top squark masses less than 890 (1000) GeV for the electron (muon) channel are excluded for the first time in models with a single nonzero R-parity violating coupling View the MathML sourceλijk′(i,j,k≤2)(i,j,k≤2), where i,j,ki,j,k correspond to the three generations

    Measurement of the Zγ→νν‾γ production cross section in pp collisions at s=8 TeV and limits on anomalous ZZγ and Zγγ trilinear gauge boson couplings

    Get PDF
    An inclusive measurement of the Zγ→νν‾γ production cross section in pp collisions at s=8TeV is presented, using data corresponding to an integrated luminosity of 19.6 fb −1 collected with the CMS detector at the LHC. This measurement is based on the observation of events with large missing energy and with a single photon with transverse momentum above 145 GeV and absolute pseudorapidity in the range |η|<1.44 . The measured Zγ→νν‾γ production cross section, 52.7±2.1 (stat)±6.4 (syst)±1.4 (lumi) fb , agrees well with the standard model prediction of 50.0−2.2+2.4 fb . A study of the photon transverse momentum spectrum yields the most stringent limits to date on the anomalous ZZγ and Zγγ trilinear gauge boson couplings

    Correlations between jets and charged particles in PbPb and pp collisions at root s(NN)=2.76 TeV

    Get PDF
    Peer reviewe

    EVOLUTIONARY TRENDS IN THE GENUS GINKGO

    No full text

    Protodammara reimatamoriori, a new species of conifer (Cupressaceae) from the Upper Cretaceous Tupuangi Formation, Chatham Islands, Zealandia

    No full text
    Isolated conifer female reproductive structures are common fossil elements from Cenomanian (ca 99–94 Ma) charcoal- and resin-rich beds of theTupuangi Formation, Chatham Islands, southwest Pacific Ocean. Recent findings have proposed that these are the oldest fossil evidence of serotiny,a highly successful fire-adaptive reproductive strategy common among tree species living in fire-prone areas today. Herein, we systematicallydescribe the external morphological and anatomical features of these fossils, by employing a combination of manual extraction and neutron tomographytechniques. We propose a new species of conifer, Protodammara reimatamoriori, and a re-examination of fossil material of the Protodammaratype species facilitated an emendation of the genus. Protodammara shares numerous features with extant Cunninghamia, Taiwania, Athrotaxis, andseveral extinct taxa of Cupressaceae, and is interpreted as an extinct lineage of the early-divergent ‘taxodioid Cupressaceae’ stem group.Funders:Australian Nuclear Science and Technology OrganisationNational Geographic</p

    Retirada do fósforo suplementar na estação seca para vacas Nelore em pastejo

    Get PDF
    O objetivo deste trabalho foi avaliar o desempenho reprodutivo de vacas Nelore em pastos de capim-marandu, após a retirada do fosfato bicálcico da mistura mineral, na estação seca. Sessenta matrizes receberam, durante seis anos, mistura mineral completa na estação chuvosa. Na estação seca, os tratamentos consistiram de: mistura mineral completa (MMC); MMC sem fosfato bicálcico (MM); e MM + concentrado. As pastagens foram manejadas de forma a não limitar a disponibilidade de matéria seca. A retirada do fosfato bicálcico do suplemento mineral, durante a estação seca, não prejudicou o desempenho reprodutivo de vacas, avaliado pela taxa de prenhez, intervalo de partos e retorno da atividade cíclica ovariana. Vacas que receberam concentrado na estação seca pariram em melhor condição corporal; vacas primíparas arraçoadas apresentaram menor número de dias vazios do que as vacas primíparas dos demais tratamentos. A retirada do fosfato bicálcico suplementar, fonte de fósforo e cálcio, na estação seca, não prejudica o desempenho de vacas multíparas em pastejo de capim-marandu
    corecore