8 research outputs found

    Search for jet extinction in the inclusive jet-pT spectrum from proton-proton collisions at s=8 TeV

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    Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.The first search at the LHC for the extinction of QCD jet production is presented, using data collected with the CMS detector corresponding to an integrated luminosity of 10.7  fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The extinction model studied in this analysis is motivated by the search for signatures of strong gravity at the TeV scale (terascale gravity) and assumes the existence of string couplings in the strong-coupling limit. In this limit, the string model predicts the suppression of all high-transverse-momentum standard model processes, including jet production, beyond a certain energy scale. To test this prediction, the measured transverse-momentum spectrum is compared to the theoretical prediction of the standard model. No significant deficit of events is found at high transverse momentum. A 95% confidence level lower limit of 3.3 TeV is set on the extinction mass scale

    Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV

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    Searches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino pair production in which each neutralino decays either to a Higgs boson (h) and an LSP or to a Z boson and an LSP, leading to hh, hZ, and ZZ states with missing transverse energy (E-T(miss)). A second aspect is chargino-neutralino pair production, leading to hW states with E-T(miss). The decays of a Higgs boson to a bottom-quark pair, to a photon pair, and to final states with leptons are considered in conjunction with hadronic and leptonic decay modes of the Z and W bosons. No evidence is found for supersymmetric particles, and 95% confidence level upper limits are evaluated for the respective pair production cross sections and for neutralino and chargino mass values

    Search for the associated production of the Higgs boson with a top-quark pair

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    Search for new physics in events with same-sign dileptons and jets in pp collisions at \sqrts = 8 TeV

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    Measurement of the t \bart production cross section in the dilepton channel in pp collisions at \sqrts = 8 TeV

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    Search for Standard Model Production of Four Top Quarks in the Lepton + Jets Channel in pp Collisions at \sqrts = 8 TeV

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    Measurement of jet multiplicity distributions in \mathrm t\overline\mathrm t production in pp collisions at \sqrts = 7\,\text TeV

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    Confirmation of the association between high levels of immunoglobulin E food sensitization and eczema in infancy: an international study

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    Background Studies of Australian infants have reported that more than 80% of those with moderate atopic eczema (AE) have high levels of IgE food sensitization (IgE-FS) that are commonly associated with IgE food allergy. Objectives To explore the relationship between high levels of IgE-FS and AE in a large cohort of young children with eczema participating in a multi-centre, international study. Methods Two thousand one hundred and eighty-four subjects (mean age 17.6 months, range 11.8-25.4; 1246 males) with active eczema from atopic families from 94 centres in 12 countries were studied. Clinical history, Scoring Atopic Dermatitis index as a measure of eczema severity and CAP-FEIA measurements for total IgE and IgE antibody levels to cow milk, egg and peanut were entered into a database. If CAP-FEIA levels exceeded previously reported age-specific cut-off levels for 95% positive predictive values (PPVs) for food allergy, subjects were defined as having high-risk IgE-FS (HR-IgE-FS). Results Serum was available from 2048 patients; 55.5% were atopic. The frequency of HR-IgE-FS to milk, egg and/or peanut was the greatest in patients whose eczema developed in the first 3 months of life and the least in those whose eczema developed after 12 months (P < 0.0001). In a regression analysis to allow for potential confounding factors, children with HR-IgE-FS had the most severe eczema and the youngest age of onset (P < 0.001); 64% of infants with severe eczema of onset-age <3 months had HR-IgE-FS. Conclusion Early-onset severe eczema in infancy was associated with HR-IgE-FS. Clinical implications Food allergies should be routinely assessed in infants with moderate or severe eczema. Capsule summary In eczematous infants, the earlier the age of onset, and the greater the severity of eczema, the greater the frequency of associated high levels of IgE-FS
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