Listar Ciencias Exactas y Naturales por título
Mostrando ítems 784-803 de 5972
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CMS PYTHIA 8 colour reconnection tunes based on underlying-event data
(2023) [Artículo de periódico]New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia 8 event generator, are obtained based on the default CMS pythia 8 underlying-event ... -
Co/ag multilayer film : role of annealing on the magnetic properties
(1992) [Artículo de periódico]Co( 15 A)/Ag(60 A) multilayers produced by electron beam deposition on a 50 A chromium buffer layer over a Si( 111) wafer have been studied by magnetoresistance, saturation magnetization, coercivity, and anisotropy. Annealing ... -
Coarse-grained models of stripe forming systems : phase diagrams, anomalies, and scaling hypothesis
(2012) [Artículo de periódico]Two coarse-grained models which capture some universal characteristics of stripe forming systems are studied. At high temperatures, the structure factors of both models attain their maxima on a circle in reciprocal space, ... -
Coarsening of three-dimensional grains in crystals, or bubbles in dry foams, tends towards a universal, statistically scale-invariant regime
(2006) [Artículo de periódico]We perform extensive Potts model simulations of three-dimensional dry foam coarsening. Starting with 2.25 million bubbles, we have enough statistics to fulfill the three constraints required for the study of statistical ... -
Co-cubstitution effects on the Fe valence in the BaFe2As2 superconducting compound : a study of hard x-ray absorption spectroscopy
(2011) [Artículo de periódico]The Fe K x-ray absorption near edge structure of BaFe₂-xCoxAs₂ superconductors was investigated. No appreciable alteration in shape or energy position of this edge was observed with Co substitution. This result provides ... -
Coeficiente de fidedignidade de um instrumento de medida
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Coexistence and crossover phenomena in a Fermi-like model of particles in counterflowing streams
(2020) [Artículo de periódico]In this work, we propose a two-dimensional extension of a previously defined one-dimensional version of a model of particles in counterflowing streams, which considers an adapted Fermi-Dirac distribution to describe the ... -
Coexistence of halloysite and kaolinite: a study on the genesis of kaolin clays of Campo Alegre basin, Santa Catarina State, Brazil
(2007) [Artículo de periódico]O caolim da Bacia de Campo Alegre, Estado de Santa Catarina, Brasil, formou-se da alteração de rochas vulcânicas ácidas. A haloisita predomina na fração argila da matriz do corpo de caolim, enquanto a caolinita, de baixa ... -
Coherence and incoherence in extended broadband triplet interaction
(2008) [Artículo de periódico]We study the transition from coherent to incoherent dynamics in a nonlinear triplet of broadband combs of waves. Expanding the analysis of previous works, we investigate what happens when the band of available modes is ... -
Coherence–incoherence transition in nonlinear wave interactions
(2005) [Artículo de periódico]In this paper we analyze the transition from coherent to incoherent wave dynamics in a broad-band triplet interaction, where, in contrast to previous models, wave vector selection rules are imposed on the nonlinear terms ... -
Coherence in scale-free networks of chaotic maps
(2004) [Artículo de periódico]We study fully synchronized states in scale-free networks of chaotic logistic maps as a function of both dynamical and topological parameters. Three different network topologies are considered: (i) a random scalefree ... -
Coherent and incoherent production of vector mesons in ultraperipheral collisions of xenon ions within the QCD parton saturation approach
(2018) [Artículo de periódico]In this paper, we analyze the exclusive vector meson photoproduction in the recent run using xenon ions at energy of 5.44 TeV performed by the Large Hadron Collider. We focus on the ultraperipheral collisions and provide ... -
Coherent and incoherent radiation from free-electron lasers with an axial guide field
(1981) [Artículo de periódico]The spontaneous and induced emission from a free-electron laser is treated for the case in which an axial magnetic field is imposed in addition to the helical, axially periodic wiggler magnetic field. The classes of possible ... -
Coherent and incoherent Upsilon production in ultraperipheral collisions at the Large Hadron Collider
(2017) [Artículo de periódico]The exclusive photoproduction of ϒðnSÞ states was calculated in ultraperipheral collisions for coherent and incoherent process in PbPb at sNN p ¼ 5.5 TeV. Different dipole models were compared in the theoretical framework ... -
Coherent J/ψ and ψ' photoproduction at midrapidity in ultra-peripheral Pb–Pb collisions at √sNN = 5.02 TeV
(2021) [Artículo de periódico]The coherent photoproduction of J/ψ and ψ' mesons was measured in ultra-peripheral Pb–Pb collisions at a center-of-mass energy √sNN = 5.02 TeV with the ALICE detector. Charmonia are detected in the central rapid ity region ... -
Coherent J/ψ photoproduction at forward rapidity in ultra-peripheral Pb–Pb collisions at √sNN=5.02 TeV
(2019) [Artículo de periódico]The ALICE collaboration performed the first rapidity-differential measurement of coherent J/ψ photoproduction in ultra-peripheral Pb–Pb collisions at a center-of-mass energy √sNN=5.02 TeV. The J/ψ is detected via its dimuon ... -
Coherent photon-hadron interactions in pA collisions : small-x physics after HERA
(2006) [Artículo de periódico]In this paper we study the photoproduction of heavy quarks and vector mesons in the coherent proton-nucleus (pA) interactions for RHIC and LHC energies and analyze if these processes can be used to determine the QCD dynamics ... -
Coherent photoproduction of ρ0 vector mesons in ultra-peripheral Pb-Pb collisions at √sNN = 5.02 TeV
(2020) [Artículo de periódico]Cross sections for the coherent photoproduction of ρ0 vector mesons in ultra-peripheral Pb-Pb collisions at sNN√ = 5.02 TeV are reported. The measurements, which rely on the π+π− decay channel, are presented in three regions ... -
Cohort study protocol of the Brazilian collaborative research network on COVID-19 : strengthening WHO global data
(2022) [Artículo de periódico]Introduction: with the COVID-19 pandemic, hospitals in low-income countries were faced with a triple challenge. First, a large number of patients required hospitalisation because of the infection’s more severe symptoms. ...