Search for decay of a fermiophobic higgs boson hf→ y y with the D0 detector at s=1.96a TeV

We report the results of a search for a narrow resonance decaying into two photons in 1.1fb-1 of data collected by the D0 experiment at the Fermilab Tevatron Collider during the period 20022006. We find no evidence for such a resonance and set a lower limit on the mass of a fermiophobic Higgs boson of mhf>100GeV at the 95% C.L. This exclusion limit exceeds those obtained in previous searches at the Fermilab Tevatron and covers a significant region of the parameter space B(hf→I I ) vs mhf which was not accessible at the CERN Large Electron-Positron Collider. © 2008 The American Physical Society.

Search for resonant t̄t production in lepton+jets events in pp collisions at √s=7 TeV

A model-independent search for the production of heavy resonances decaying into top-antitop quark pairs is presented. The search is based on events containing one lepton (muon or electron) and at least two jets selected from data samples corresponding to an integrated luminosity of 4.4-5.0 fb -1 collected in pp collisions at √s =7 TeV. Results are presented from the combination of two dedicated searches optimized for boosted production and production at threshold. No excess of events is observed over the expected yield from the standard model processes. Topcolor Z′ bosons with narrow (wide) width are excluded at 95% confidence level for masses below 1.49 (2.04) TeV and an upper limit of 0.3 (1.3) pb or lower is set on the production cross section times branching fraction for resonance masses above 1 TeV. Kaluza-Klein excitations of a gluon with masses below 1.82 TeV (at 95% confidence level) in the Randall-Sundrum model are also excluded, and an upper limit of 0.7 pb or lower is set on the production cross section times branching fraction for resonance masses above 1 TeV.[Figure not available: See fulltext.] © 2012 CERN for the benefit of the CMS collaboration.

Measurement of the sum of WW and WZ production with W+dijet events in pp collisions at √s = 7 TeV

A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at √s = 7 TeV with the CMS detector at the LHC, corresponds to an integrated luminosity of 5. 0 fb-1. The measured value of the sum of the inclusive WW and WZ cross sections is σ(pp→WW+WZ)=68. 9±8. 7 (stat.)±9. 7 (syst.)±1. 5 (lum.) pb, consistent with the standard model prediction of 65. 6±2. 2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes. © 2013 CERN for the benefit of the CMS collaboration.

Measurement of the tt̄ production cross section in the τ+jets channel in pp collisions at √s = 7 TeV

The top-quark pair production cross section in 7 TeV center-of-mass energy proton-proton collisions is measured using data collected by the CMS detector at the LHC. The measurement uses events with one jet identified as a hadronically decaying τ lepton and at least four additional energetic jets, at least one of which is identified as coming from a b quark. The analyzed data sample corresponds to an integrated luminosity of 3.9 fb-1 recorded by a dedicated multijet plus hadronically decaying τ trigger. A neural network has been developed to separate the top-quark pairs from the W+jets and multijet backgrounds. The measured value of σtt̄= 152 ± 12,(stat.) ± 32,(syst.) ±,(lum.) pb is consistent with the standard model predictions. © 2013 CERN for the benefit of the CMS collaboration.

Search for pair-produced dijet resonances in four-jet final states in pp collisions at √s=7 TeV

A search for the pair production of a heavy, narrow resonance decaying into two jets has been performed using events collected in √s=7 TeV pp collisions with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb-1. Events are selected with at least four jets and two dijet combinations with similar dijet mass. No resonances are found in the dijet mass spectrum. The upper limit at 95% confidence level on the product of the resonance pair production cross section, the branching fractions into dijets, and the acceptance varies from 0.22 to 0.005 pb, for resonance masses between 250 and 1200 GeV. Pair-produced colorons decaying into qq̄ are excluded for coloron masses between 250 and 740 GeV. © 2013 CERN. citation, and DOI.

Search for narrow resonances using the dijet mass spectrum in pp collisions at √s=8 TeV

Results are presented of a search for the production of new particles decaying to pairs of partons (quarks, antiquarks, or gluons), in the dijet mass spectrum in proton-proton collisions at √s=8 TeV. The data sample corresponds to an integrated luminosity of 4.0 fb-1, collected with the CMS detector at the LHC in 2012. No significant evidence for narrow resonance production is observed. Upper limits are set at the 95% confidence level on the production cross section of hypothetical new particles decaying to quark-quark, quark-gluon, or gluon-gluon final states. These limits are then translated into lower limits on the masses of new resonances in specific scenarios of physics beyond the standard model. The limits reach up to 4.8 TeV, depending on the model, and extend previous exclusions from similar searches performed at lower collision energies. For the first time mass limits are set for the Randall-Sundrum graviton model in the dijet channel. © 2013 CERN. Published by the American Physical Society under the terms of the http://creativecommons.org/licenses/by/3.0/ Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Search for physics beyond the standard model in events with τ leptons, jets, and large transverse momentum imbalance in pp collisions at √s = 7 TeV

A search for physics beyond the standard model is performed with events having one or more hadronically decaying τ leptons, highly energetic jets, and large transverse momentum imbalance. The data sample corresponds to an integrated luminosity of 4.98 fb-1 of proton-proton collisions at √ = 7 TeV collected with the CMS detector at the LHC in 2011. The number of observed events is consistent with predictions for standard model processes. Lower limits on the mass of the gluino in supersymmetric models are determined. © 2013 CERN for the benefit of the CMS collaboration.

Scale-invariant resonance tagging in multijet events and new physics in Higgs pair production

We study resonant pair production of heavy particles in fully hadronic final states by means of jet substructure techniques. We propose a new resonance tagging strategy that smoothly interpolates between the highly boosted and fully resolved regimes, leading to uniform signal efficiencies and background rejection rates across a broad range of masses. Our method makes it possible to efficiently replace independent experimental searches, based on different final state topologies, with a single common analysis. As a case study, we apply our technique to pair production of Higgs bosons decaying into b\overline{b} pairs in generic New Physics scenarios. We adopt as benchmark models radion and massive KK graviton production in warped extra dimensions. We find that despite the overwhelming QCD background, the 4b final state has enough sensitivity to provide a complementary handle in searches for enhanced Higgs pair production at the LHC. © 2013 SISSA.

Search for exotic resonances in diboson final states with the CMS detector at the LHC

The results of searches for new resonances decaying to a pair of massive vector bosons (WW, WZ, ZZ) are presented. All searches are performed using 5.0 fb-1 of proton-proton collisions, at TeV of center of mass energy, collected by the Compact Muon Solenoid detector at the Large Hadron Collider. No significant excess compared to the standard model background expectation is observed, and upper limits at 95% confidence level are set on the production cross section times the branching fraction of hypothetical particles decaying to a pair of vector bosons. The results are interpreted in the context of several benchmark models, such as the Randall-Sundrum gravitons, the Sequential Standard Model W′, and Technicolor. Graviton resonances in the Randall-Sundrum model with masses smaller than 940 GeV/c2, for coupling parameter k/MPl = 0.05 are excluded. Bulk (ADPS) Randall-Sundrum gravitons with masses smaller than 610 GeV/c2 are excluded, for k/MPl = 0.05. Sequential Standard Model W′ with masses smaller than 1143 GeV/c2 are excluded, as well as ρTC in the 167-687 GeV/c2 mass range, in Low Scale Technicolor models with M(πTC) = 3/4 M(ρTC) - 25 GeV/c2. © 2013 IOP Publishing Ltd.

Isolamento de linhagens microbianas termofílicas amilolíticas, produção, caracterização e aplicação das amilases na hidrólise do amido de mandioca

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Degradação fotocatalítica na redução da DQO (demanda química de oxigênio) de efluente proveniente de processos de extração vegetal

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Perfil de progestinas fecais durante a gestação de veado-campeiro (Ozotoceros bezoarticus) no Pantanal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Busca por ressonâncias de grávitons em modelos com dimensões extras no LHC

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cryptococcus neoformans de fontes ambientais e biopropecção de extratos de plantas com atividade saneante

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Polinização de Cacauí (Theobroma speciosum Willd. ex Spreng. - Sterculiaceae): implicações para conservação

O cacauí (Theobroma speciosum) é uma fruteira típica da Região Norte, cujas flores sapromiofílicas atraem dípteros. Os recursos que os insetos utilizam são muito variados e entre eles estão as flores, as quais podem ser utilizadas como alimento e local para reprodução. Este trabalho visou fazer uma comparação do sistema de polinização de T. speciosum em duas áreas de preservação distintas, contribuindo para a avaliação das estratégias de conservação da espécie. O trabalho foi realizado nos anos de 2000 a 2002, no Centro de Pesquisa do Trópico Úmido da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA/CPATU) e na Estação Científica Ferreira Penna (ECFPn/MPEG). Foram realizados estudos sobre estrutura populacional e fenologia de T. speciosum nas duas áreas de preservação, observação comportamental dos insetos no campo, coletas de insetos visitantes das flores de cacauí, análise de carreamento de pólen pelos insetos e verificação dos insetos emergentes no laboratório. As árvores de cacauí, em ambos os locais, florescem em períodos mais secos e frutificam em períodos mais úmidos. As populações de cacauí nas duas áreas diferem pela distribuição espacial e etária dos seus indivíduos. A falta de jovens e subadultos na área de preservação ex situ, mostra falha no "tum over' populacional, demonstrando fragilidade no sistema estabelecido. As inflorescências de T. speciosum são utilizadas por uma grande diversidade de invertebrados. Nove ordens de insetos, e pelo menos duas ordens de outros invertebrados, visitaram as flores de cacau'. As ordens com maior quantidade de indivíduos foram Hymenoptera, Thysanoptera, Diptera e Coleoptera. Os visitantes das flores de cacauí foram classificados como: oportunistas, predadores e polinizadores. Drosofilideos foram indicados como polinizadores de T speciosum, com a possibilidade da participação de alguns forídeos. As guildas dos drosofilídeos foram distintas nas duas áreas de preservação e mais diversa na área de preservação in situ. Quatro espécies foram comuns as duas áreas. A perda de diversidade e alteração na composição na guilda de polinizadores parece não ter afetado a população de T. speciosum na área de preservação ex situ. No caso em estudo o sistema de polinização apesar de profundamente alterado, ainda apresenta sinais de viabilidade.