Measurement of the production cross section for Z gamma -> nu(nu)over-bar gamma in pp collisions at √s=7 TeV and limits on ZZ gamma and Z gamma gamma triple gauge boson couplings

This article is the pre-print version of the final published paper that is available from the link below.A measurement of the Z → vvγ cross section in pp collisions at root s = 7TeV is presented, using data corresponding to an integrated luminosity of 5.0 fb-1 collected with the CMS detector. This measurement is based on the observation of events with an imbalance of transverse energy in excess of 130 GeV and a single photon in the absolute pseudorapidity range |n| < 1:4 with transverse energy above 145 GeV. The Z →vvγ production cross section is measured to be 21.1±4.2 (stat:)±4.3 (syst:)±0.5 (lum:) fb, which agrees with the standard model prediction of 21.9±1.1 fb. The results are combined with the CMS measurement of Z production in the l+l- γ final state (where l is an electron or a muon) to yield the most stringent limits to date on triple gauge boson couplings: |hZ3|< 2.7 x 10-3, |hZ4| < 1,3 x 10-5 for ZZγ and |hγ3| < 2.9 x10-3, |hγ4| < 1.5 x 10-5 for Zγγ couplings

Measurements of the t(t)over-bar production cross section in lepton plus jets final states in pp collisions at 8 and ratio of 8 to 7 TeV cross sections

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Search for lepton flavour violating decays of the Higgs boson to eτand eμin proton–proton collisions at √s=8TeV

A direct search for lepton flavour violating decays of the Higgs boson (H) in the H →eτand H →eμchannels is described. The data sample used in the search was collected in proton–proton collisions at √s=8TeVwith the CMS detector at the LHC and corresponds to an integrated luminosity of 19.7fb−1. No evidence is found for lepton flavour violating decays in either final state. Upper limits on the branching fractions, B(H →eτ) <0.69%and B(H →eμ) <0.035%, are set at the 95% confidence level. The constraint set on B(H →eτ)is an order of magnitude more stringent than the existing indirect limits. The limits are used to constrain the corresponding flavour violating Yukawa couplings, absent in the standard model

Measurement of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section in pp collisions at root s=7 TeV and first determination of the strong coupling constant in the TeV range

A measurement is presented of the ratio of the inclusive 3-jet cross section to the inclusive 2-jet cross section as a function of the average transverse momentum, , of the two leading jets in the event. The data sample was collected during 2011 at a proton-proton centre-of-mass energy of 7 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 5.0 fb(-1). The strong coupling constant at the scale of the Z boson mass is determined to be alpha(S)(M-Z) = 0.1148 +/- 0.0014 (exp.) +/- 0.0018 (PDF) +/- 0.0050 (theory), by comparing the ratio in the range 0.42 < 1.39 TeV to the predictions of perturbative QCD at next-to-leading order. This is the first determination of alpha(S)(M-Z) from measurements at momentum scales beyond 0.6 TeV. The predicted ratio depends only indirectly on the evolution of the parton distribution functions of the proton such that this measurement also serves as a test of the evolution of the strong coupling constant. No deviation from the expected behaviour is observed

Evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons

A search for a standard model Higgs boson decaying into a pair of tau leptons is performed using events recorded by the CMS experiment at the LHC in 2011 and 2012. The dataset corresponds to an integrated luminosity of 4.9 fb(-1) at a centre-of-mass energy of 7 TeV and 19.7 fb(-1) at 8 TeV. Each tau lepton decays hadronically or leptonically to an electron or a muon, leading to six different final states for the tau-lepton pair, all considered in this analysis. An excess of events is observed over the expected background contributions, with a local significance larger than 3 standard deviations for m (H) values between 115 and 130 GeV. The best fit of the observed H -> tau tau signal cross section times branching fraction for m(H) = 125 GeV is 0.78 +/- 0.27 times the standard model expectation. These observations constitute evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons

Search for physics beyond the standard model in events with two leptons of same sign, missing transverse momentum, and jets in proton-proton collisions at root s=13TeV

A data sample of events from proton–proton collisions with two isolated same-sign leptons, missing transverse momentum, and jets is studied in a search for signatures of new physics phenomena by the CMS Collaboration at the LHC. The data correspond to an integrated luminosity of 35.9 fb−1, and a center-of-mass energy of 13 TeV. The properties of the events are consistent with expectations from standard model processes, and no excess yield is observed. Exclusion limits at 95% confidence level are set on cross sections for the pair production of gluinos, squarks, and same-sign top quarks, as well as top-quark associated production of a heavy scalar or pseudoscalar boson decaying to top quarks, and on the standard model production of events with four top quarks. The observed lower mass limits are as high as 1500 GeV for gluinos, 830 GeV for bottom squarks. The excluded mass range for heavy (pseudo)scalar bosons is 350–360 (350–410) GeV. Additionally, model-independent limits in several topological regions are provided, allowing for further interpretations of the results

Inclusive and differential measurements of the t(t)over-bar charge asymmetry in pp collisions at root s=8 TeV

The charge asymmetry is measured in proton–proton collisions at a centre-of-mass energy of . The data, collected with the CMS experiment at the LHC, correspond to an integrated luminosity of 19.7 fb−1. Selected events contain an electron or a muon and four or more jets, where at least one jet is identified as originating from b-quark hadronization. The inclusive charge asymmetry is found to be . In addition, differential charge asymmetries as a function of rapidity, transverse momentum, and invariant mass of the system are studied. For the first time at the LHC, the measurements are also performed in a reduced fiducial phase space of top quark pair production, with an integrated result of . All measurements are consistent within two standard deviations with zero asymmetry as well as with the predictions of the standard model

Ongoing Strategies to Improve Antimicrobial Utilization in Hospitals across the Middle East and North Africa (MENA): Findings and Implications

Antimicrobial resistance (AMR) is an increasing global concern, increasing costs, morbidity, and mortality. National action plans (NAPs) to minimize AMR are one of several global and national initiatives to slow down rising AMR rates. NAPs are also helping key stakeholders understand current antimicrobial utilization patterns and resistance rates. The Middle East is no exception, with high AMR rates. Antibiotic point prevalence surveys (PPS) provide a better understanding of existing antimicrobial consumption trends in hospitals and assist with the subsequent implementation of antimicrobial stewardship programs (ASPs). These are important NAP activities. We examined current hospital consumption trends across the Middle East along with documented ASPs. A narrative assessment of 24 PPS studies in the region found that, on average, more than 50% of in-patients received antibiotics, with Jordan having the highest rate of 98.1%. Published studies ranged in size from a single to 18 hospitals. The most prescribed antibiotics were ceftriaxone, metronidazole, and penicillin. In addition, significant postoperative antibiotic prescribing lasting up to five days or longer was common to avoid surgical site infections. These findings have resulted in a variety of suggested short-, medium-, and long-term actions among key stakeholders, including governments and healthcare workers, to improve and sustain future antibiotic prescribing in order to decrease AMR throughout the Middle East

Adecuación del primer curso de los estudios de Informática al Espacio Europeo de Educación Superior

A measurement of the Lambda(0)(b) lifetime using the decay Lambda(0)(b) -> J/psi Lambda in protonproton collisions at root s = 7TeV is presented. The data set, corresponding to an integrated luminosity of about 5 fb(-1), was recorded with the CMS experiment at the Large Hadron Collider using triggers that selected dimuon events in the J/psi mass region. The Lambda(0)(b) lifetime is measured to be 1.503 +/- 0.052 (stat.) +/- 0.031 (syst.) psBMWF ; FWF ; FNRS ; FWO ; CNPq ; CAPES ; FAPERJ ; FAPESP ; MEYS ; CERN ; CAS ; MoST ; NSFC ; COLCIENCIAS ; MSES ; RPF ; MoER ; SF0690030s09 ; ERDF ; Academy of Finland ; MEC ; HIP ; CEA ; CNRS/IN2P3 ; BMBF ; DFG ; HGF ; GSRT ; OTKA ; NKTH ; DAE ; DST ; IPM ; SFI ; INFN ; NRF ; WCU ; LAS ; CINVESTAV ; CONACYT ; SEP ; UASLP-FAI ; MSI ; PAEC ; MSHE ; NSC ; FCT ; JINR ; MON ; RosAtom ; RAS ; RFBR ; MSTD ; SEIDI ; CPAN ; Swiss Funding Agencies ; NSC ; ThEPCenter ; IPST ; NSTDA ; TUBITAK ; TAEK ; NASU ; STFC ; University of California Institute for Mexico and the United States ; the Marie-Curie programme and the European Research Council and EPLANET ; DOE and NSF ; the Leventis Foundation ; the A. P. Sloan Foundation ; the Alexander von Humboldt Foundation ; the Belgian Federal Science Policy Office ; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture ; the Agentschap voor Innovatie door Wetenschap en Technologie ; the Ministry of Education ; Youth and Sports of Czech Republic ; the Agence Nationale de la Recherche ANR-12-JS05-002-01 ; the Council of Science and Industrial Research ; India; the Compagnia di San Paolo ; the HOMING PLUS programme of Foundation for Polish Science cofinanced by EU ; Regional Development Fund ; the Thalis and Aristeia programmes cofinanced by EU-ESF and the Greek NSRF.

Simulations of Flow Over Wind Turbines

One of the most abundant sources of renewable energy is wind. Today, a considerable amount of resources are being utilized for research on harnessing the wind energy efficiently. Out of all the factors responsible for efficient energy production, the aerodynamics of flow around the wind turbine blades play an important role. This work aims to undertake aerodynamic analysis of a Horizontal Axis Wind Turbine. A steady state, incompressible flow solver for multiple reference frames, MRFSimple- Foam is modified and used for performing simulations of flow over National Renewable Energy Laboratory Phase VI wind turbine rotor. The code is first tested on a locally modeled wind turbine blade and is then validated by using the actual NREL rotor. The flow behavior is studied and a comparison of results from the simulations and the experimental wind tunnel data is presented. The ability of Computational Fluid Dynamics (CFD) techniques in simulating wind flow over entire wind turbine assembly is also displayed by carrying out moving mesh simulations of a full wind turbine