Search results for "Computations"

showing 10 items of 35 documents

Forward dijets in proton-nucleus collisions at next-to-leading order: the real corrections

2021

Using the CGC effective theory together with the hybrid factorisation, we study forward dijet production in proton-nucleus collisions beyond leading order. In this paper, we compute the "real" next-to-leading order (NLO) corrections, i.e. the radiative corrections associated with a three-parton final state, out of which only two are being measured. To that aim, we start by revisiting our previous results for the three-parton cross-section presented in our previous paper. After some reshuffling of terms, we deduce new expressions for these results, which not only look considerably simpler, but are also physically more transparent. We also correct several errors in this process. The real NLO …

High Energy Physics - Theorydijet: productionNuclear and High Energy PhysicsParticle physicsNuclear TheoryProton[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]splittingFOS: Physical sciencescollinearParton01 natural sciencesColor-glass condensateNuclear Theory (nucl-th)DGLAP equationHigh Energy Physics - Phenomenology (hep-ph)FactorizationfactorizationNLO Computations0103 physical sciencesRadiative transferEffective field theoryradiative correctionlcsh:Nuclear and particle physics. Atomic energy. Radioactivitypartonheavy ion phenomenology010306 general physicsp nucleus: scatteringPhysicsNLO computationshybrid010308 nuclear & particles physics[PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th]higher-order: 1Heavy Ion PhenomenologyGluonHigh Energy Physics - PhenomenologyDGLAPHigh Energy Physics - Theory (hep-th)kinematics[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]color glass condensatelcsh:QC770-798
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On osculation, superosculation and characteristic points. Addenda: Computations

1943

differential geometry computations
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On the effect of analog noise in discrete-time analog computations

1998

We introduce a model for analog computation with discrete time in the presence of analog noise that is flexible enough to cover the most important concrete cases, such as noisy analog neural nets and networks of spiking neurons. This model subsumes the classical model for digital computation in the presence of noise. We show that the presence of arbitrarily small amounts of analog noise reduces the power of analog computational models to that of finite automata, and we also prove a new type of upper bound for the VC-dimension of computational models with analog noise.

Computational modelFinite-state machineArtificial neural networkComputer scienceCognitive NeuroscienceComputationanalog noiseAnalog signal processingUpper and lower boundsArts and Humanities (miscellaneous)Discrete time and continuous timeNoise (video)Algorithmanalog computations
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A model for designing callable bonds and its solution using tabu search

1997

Abstract We formulate the problem of designing callable bonds as a non-linear, global, optimization problem. The data of the model are obtained from simulations of holding-period returns of a given bond design, which are used to compute a certainty equivalent return, viz., some target assets. The design specifications of the callable bond are then adjusted so that the certainty equivalent return is maximized. The resulting problem is multi-modal, and a tabu search procedure, implemented on a distributed network of workstations, is used to optimize the bond design. The model is compared with the classical portfolio immunization model, and the tabu search solution technique is compared with s…

Economics and EconometricsMathematical optimizationControl and OptimizationOptimization problemApplied MathematicsImmunization (finance)Tabu searchCallable bondTabu searchCallable bondsProduct designParallel computationsSimulated annealingEconomicsPortfolioFinancial innovationHill climbingGlobal optimizationSimulation
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Theoretical study of a hydration mechanism in an enaminone pro-drug prototype

2003

Enaminones may act as pro-drugs releasing via proton-catalyzed hydrolysis a primary amine, which may be an actual drug. A hydration mechanism of prototype enaminone (2-propenal-3-amine) has been subjected to quantum chemical studies. All involved compounds were investigated in a search for the most likely reactive form. Results revealed that the proposed reaction pathway is thermodynamically possible.

Quantum chemicalHydrolysisPrimary (chemistry)ChemistryComputational chemistryAb initio computationsAmine gas treatingPhysical and Theoretical ChemistryProdrugCondensed Matter PhysicsBiochemistryMechanism (sociology)Journal of Molecular Structure: THEOCHEM
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Weak intermolecular interactions promote blue luminescence of protonated 2,2′-dipyridylamine salts

2014

In this work we demonstrate that protonation and π-stacking can be exploited to convert non-luminescent 2,2′-dipyridylamine into blue-emitting derivatives. We have synthesized a series of luminescent 2,2′-dipyridylamine (dpa) salts, i.e., (dpaH)X·nSolv (dpa = 2,2′-dipyridylamine, X = HF2, n = 0.5, Solv = H2O 1; X = Cl, n = 2, Solv = H2O 2; X = Br, n = 2, Solv = H2O 3; X = I n = 1, Solv = H2O 4a; X = I n = 1, Solv = CHCl34b), (dpaH)2[SiF6]·H2O 5 and (dpaH)X (X = I36; SbF67; BF48) and characterized their emission properties, both in the solid-state and in solution. To rationalize our observations and relate the luminescence properties to the structure in the solid state and in solution, we ha…

Steric effectsChemistryHydrogen bondIntermolecular forceSolid-stateProtonationGeneral ChemistryConical intersectionCrystallographyComputational chemistryMaterials ChemistryAb initio computationsLuminescenceta116J. Mater. Chem. C
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Tree-Loop Duality Relation beyond simple poles

2013

We develop the Tree-Loop Duality Relation for two- and three-loop integrals with multiple identical propagators (multiple poles). This is the extension of the Duality Relation for single poles and multi-loop integrals derived in previous publications. We prove a generalization of the formula for single poles to multiple poles and we develop a strategy for dealing with higher-order pole integrals by reducing them to single pole integrals using Integration By Parts.

PhysicsHigh Energy Physics - TheoryNuclear and High Energy PhysicsPure mathematics010308 nuclear & particles physicsGeneralizationPropagatorDuality (optimization)FísicaFOS: Physical sciencesExtension (predicate logic)QCD Phenomenology01 natural sciencesDuality relationLoop (topology)Theoretical physicsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - Theory (hep-th)NLO Computations0103 physical sciencesIntegration by partsddc:530Tree (set theory)010306 general physics
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Scalar particle contribution to Higgs production via gluon fusion at NLO

2007

22 pages, 5 figures.-- ISI Article Identifier: 000252243700095.-- ArXiv pre-print available at: http://arxiv.org/abs/0709.4227

Nuclear and High Energy PhysicsParticle physicsHigh Energy Physics::LatticeScalar (mathematics)Adjoint representationFOS: Physical sciencesProton-proton collisionsHiggs sectorHigh Energy Physics - Phenomenology (hep-ph)Supersymmetric spectraBoson productionNLO ComputationsHadronic CollidersPhysicsQuantum chromodynamicsGluinoLogarithmic correctionsHigh Energy Physics::PhenomenologyScalar bosonGluonHigh Energy Physics - PhenomenologyQCD correctionsSupersymmetry Phenomenology2-loop Electroweak correctionsHiggs bosonHigh Energy Physics::ExperimentHadron-hadron collisionsJournal of High Energy Physics
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Efficient parallel computations of flows of arbitrary fluids for all regimes of Reynolds, Mach and Grashof numbers

2002

This paper presents a unified numerical method able to address a wide class of fluid flow problems of engineering interest. Arbitrary fluids are treated specifying totally arbitrary equations of state, either in analytical form or through look‐up tables. The most general system of the unsteady Navier–Stokes equations is integrated with a coupled implicit preconditioned method. The method can stand infinite CFL number and shows the efficiency of a quasi‐Newton method independent of the multi‐block partitioning on parallel machines. Computed test cases ranging from inviscid hydrodynamics, to natural convection loops of liquid metals, and to supersonic gasdynamics, show a solution efficiency i…

Computations Flow FluidNatural convectionApplied MathematicsMechanical EngineeringNumerical analysisCourant–Friedrichs–Lewy conditionGrashof numberMechanicsComputer Science ApplicationsPhysics::Fluid Dynamicssymbols.namesakeClassical mechanicsMach numberMechanics of MaterialsInviscid flowFluid dynamicssymbolsSupersonic speedSettore ING-IND/19 - Impianti NucleariMathematicsInternational Journal of Numerical Methods for Heat & Fluid Flow
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Tendencies in ABO3 Perovskite and SrF2, BaF2 and CaF2 Bulk and Surface F-Center Ab Initio Computations at High Symmetry Cubic Structure

2021

This research was partly funded by the Latvian Council of Science project No. LZP‐ 2020/2‐0009 (for R. Eglitis), as well as the ERAF Project No. 1.1.1.1/18/A/073. We express our gratitude for the financial support from Latvian–Ukraine cooperation Project No. Latvia–Ukraine LV‐ UA/2021/5. The Institute of Solid State Physics, University of Latvia (Latvia), as the Centre of Excellence has received funding from the European Unions Horizon 2020 Framework Pro‐ gramme H2020‐WIDESPREAD01‐2016‐2017‐Teaming Phase2 under Grant Agreement No. 739508, project CAMART2.

Surface (mathematics)B3LYPMaterials sciencePhysics and Astronomy (miscellaneous)General Mathematicschemistry.chemical_element02 engineering and technologyABO3 high symmetry cubic perovskites01 natural sciencesElectric chargeMolecular physicsABO<sub>3</sub> high symmetry cubic perovskitesab initio computationsVacancy defect0103 physical sciencesQA1-939Computer Science (miscellaneous)010306 general physicsPerovskite (structure)<i>F</i>-centerCharge (physics)F‐center021001 nanoscience & nanotechnologySymmetry (physics)B3PWchemistryChemistry (miscellaneous):NATURAL SCIENCES [Research Subject Categories]FluorineAb initio computationsAb initio computations0210 nano-technologyMathematicsSymmetry
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