Search results for "complexi"

showing 10 items of 1116 documents

Evidence for DirectCPViolation in the Measurement of the Cabbibo-Kobayashi-Maskawa AngleγwithB∓→D(*)K(*)∓Decays

2010

We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub S}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub S}{sup 0} K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K*{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}, using 468 million B{bar B} pairs collected by the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC. We measure {gamma} = (68 {+-} 14 {+-} 4 {+-} 3){sup o} (modulo 180{sup o}), where the first error is statistica…

PhysicsAntiparticleMeson010308 nuclear & particles physicsHadronGeneral Physics and AstronomyDalitz plot01 natural sciencesCrystallographyParticle decayTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYQuantum mechanics0103 physical sciencesD mesonCP violationB meson010306 general physicsPhysical Review Letters
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Neutron-induced soft errors in advanced Flash memories

2008

Atmospheric neutrons are a known source of Soft Errors (SE), in static and dynamic CMOS memories. This paper shows for the first time that atmospheric neutrons are able to induce SE in Flash memories as well. Detailed experimental results provide an explanation linking the Floating Gate (FG) cell SE rate to the physics of the neutron-matter interaction. The neutron sensitivity is expected to increase with the number of bits per cell and the reduction of the feature size, but the SE issue is within the limit of current ECC capabilities and will remain so in the foreseeable future.

PhysicsAstrophysics::High Energy Astrophysical PhenomenaHardware_PERFORMANCEANDRELIABILITYFlash memorySEESettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Computational physicsSettore FIS/03 - Fisica della MateriaReduction (complexity)Flash (photography)CMOSLimit (music)Electronic engineeringNeutronSensitivity (control systems)Error detection and correctionneutron irradiationSEE neutron irradiation
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The S01 − Λ(1405) and − Λ(1670) resonances in meson-baryon unitarized coupled channel chiral perturbation theory

2003

Abstract The s-wave meson-baryon system with strangeness S = −1 and isospin I = 0 is studied using the Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. The needed two particle irreducible potential is taken from lowest order Chiral Perturbation Theory in a relativistic formalism. The K N, πΣ, νΛ , and KΞ two-body channels have been included. Off-shell behavior is parameterized in terms of low energy constants, which outnumber those assumed in previous works and provide a better fit to the data. The masses, widths and branching ratios of the Λ(1405) and Λ(1670) resonances are determined. In our model, we find no one but two resonances in the Λ(1405) region.

PhysicsBaryonNuclear and High Energy PhysicsParticle physicsChiral symmetryChiral perturbation theoryMesonIsospinQuantum mechanicsNuclear TheoryParameterized complexityStrangenessCommunication channelNuclear Physics A
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Two Applications of Geometric Optimal Control to the Dynamics of Spin Particles

2014

The purpose of this article is to present the application of methods from geometric optimal control to two problems in the dynamics of spin particles. First, we consider the saturation problem for a single spin system and second, the control of a linear chain of spin particles with Ising couplings. For both problems the minimizers are parameterized using Pontryagin Maximum Principle and the optimal solution is found by a careful analysis of the corresponding equations.

PhysicsClassical mechanicsChain (algebraic topology)Bloch equationsDynamics (mechanics)Mathematical analysisParameterized complexityIsing modelSaturation (chemistry)Optimal controlSpin-½
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Euclidean random matrix theory: low-frequency non-analyticities and Rayleigh scattering

2011

By calculating all terms of the high-density expansion of the euclidean random matrix theory (up to second-order in the inverse density) for the vibrational spectrum of a topologically disordered system we show that the low-frequency behavior of the self energy is given by $\Sigma(k,z)\propto k^2z^{d/2}$ and not $\Sigma(k,z)\propto k^2z^{(d-2)/2}$, as claimed previously. This implies the presence of Rayleigh scattering and long-time tails of the velocity autocorrelation function of the analogous diffusion problem of the form $Z(t)\propto t^{(d+2)/2}$.

PhysicsDensity matrixStatistical Mechanics (cond-mat.stat-mech)AutocorrelationFOS: Physical sciencesInverseDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural Networks16. Peace & justiceCondensed Matter Physics01 natural sciences010305 fluids & plasmassymbols.namesakeSelf-energyTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYQuantum mechanicsPhysical Sciences0103 physical sciencesEuclidean geometrysymbolsRayleigh scatteringDiffusion (business)010306 general physicsRandom matrixCondensed Matter - Statistical MechanicsPhilosophical Magazine
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Halo-like structure in 7He nucleus

2020

Abstract A study of the neutron structure of the ground state of 7He has been performed by means of registration and analysis of the decay channels of the residual nuclei following absorption of stopped pions. In particular, the reaction 9Be ( π − , d )X have been investigated where X denotes any system with five neutrons and two protons – the constituencies of a 7He nucleus. It was shown that the structure of 7He is determined by correlations of two neutrons in the states 6He (0+), 6He (2+) and one neutron in the shell p3/2. The 4He+3n structure is not manifested in the ground state of 7He. The obtained results are consistent with the known data on considerable mixture of configurations “6…

PhysicsDiffractionHistoryRadiusComputer Science ApplicationsEducationPionmedicine.anatomical_structureTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYExcited statemedicineNeutronHaloAtomic physicsGround stateNucleusJournal of Physics: Conference Series
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Fast Direct Solver for a Time-harmonic Electromagnetic Problem with an Application

2003

A fast direct solution of a periodic problem derived from the time-harmonic Maxwell’s equations is considered. The problem is discretized by low order hexahedral finite elements proposed by Nedelec. The solver is based on the application of FFT, and it has the computational cost O(N log N). An application to scattering of an electromagnetic wave by a periodic structure is presented.

PhysicsDiscretizationFictitious domain methodScatteringFast Fourier transformApplied mathematicsSolverElectromagnetic radiationTime complexityFinite element methodMathematics::Numerical Analysis
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No-scale D=5 supergravity from Scherk-Schwarz reduction of D=6 theories

2004

We perform a generalized dimensional reduction of six dimensional supergravity theories to five dimensions. We consider the minimal $(2,0)$ and the maximal $(4,4)$ theories. In each case the reduction allows us to obtain gauged supergravities of no-scale type in dimension five with gauge groups that escape previous classifications. In the minimal case, the geometric data of the reduced theory correspond to particular cases of the D=5 real special geometry. In the maximal case we find a four parameter solution which allows partial breaking of supersymmetry.

PhysicsHigh Energy Physics - TheoryNuclear and High Energy PhysicsScale (ratio)SupergravityDimension (graph theory)High Energy Physics::PhenomenologyFOS: Physical sciencesFísicaSupersymmetryGauge (firearms)Type (model theory)Reduction (complexity)High Energy Physics::TheoryHigh Energy Physics - Theory (hep-th)Dimensional reductionParticle Physics - TheoryMathematical physics
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Scherk-Schwarz reduction of D=5 special and quaternionic geometry

2004

We give the N=2 gauged supergravity interpretation of a generic D=4, N=2 theory as it comes from generalized Scherk-Schwarz reduction of D=5, N=2 (ungauged) supergravity. We focus on the geometric aspects of the D=4 data such as the general form of the scalar potential and masses in terms of the gauging of a ``flat group''. Higgs and super-Higgs mechanism are discussed in some detail.

PhysicsHigh Energy Physics - TheoryPhysics and Astronomy (miscellaneous)Group (mathematics)SupergravityHigh Energy Physics::LatticeGauged supergravityHigh Energy Physics::PhenomenologyFOS: Physical sciencesFísicaScalar potentialInterpretation (model theory)Reduction (complexity)High Energy Physics::TheoryHigh Energy Physics - Theory (hep-th)Higgs bosonFocus (optics)Particle Physics - TheoryMathematical physics
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Spin and charge orderings in the atomic limit of the U-V-J model

2011

In this paper we study a generalization of the 1D Hubbard model by considering density-density and Ising-type spin-spin nearest neighbor (NN) interactions, parameterized by $V$ and $J$, respectively. We present the T=0 phase diagram for both ferro ($J>0$) and anti-ferro ($J<0$) coupling obtained in the narrow-band limit by means of an extension to zero-temperature of the transfer-matrix method. Based on the values of the Hamiltonian parameters, we identify a number of phases that involve orderings of the double occupancy, NN density and spin correlations, being these latter very fragile.

PhysicsHistoryHubbard modelStrongly Correlated Electrons (cond-mat.str-el)Condensed Matter - SuperconductivityParameterized complexityFOS: Physical sciencesComputer Science ApplicationsEducationk-nearest neighbors algorithmSuperconductivity (cond-mat.supr-con)symbols.namesakeCondensed Matter - Strongly Correlated ElectronssymbolsCondensed Matter::Strongly Correlated ElectronsHamiltonian (quantum mechanics)Mathematical physicsPhase diagram
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