Search results for "SIP"

showing 10 items of 1280 documents

Muon-capture strength functions in intermediate nuclei of 0νββ decays

2019

Capture rates of ordinary muon capture (OMC) to the intermediate nuclei of neutrinoless double beta ($0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$) decays of current experimental interest are computed. The corresponding OMC (capture-rate) strength functions have been analyzed in terms of multipole decompositions. The computed low-energy OMC-rate distribution to $^{76}\mathrm{As}$ is compared with the available data of Zinatulina et al. [Phys. Rev. C 99, 024327 (2019)]. The present OMC computations are performed using the Morita-Fujii formalism by extending the original formalism beyond the leading order. The participant nuclear wave functions are obtained in extended no-core singl…

PhysicsParticle physics010308 nuclear & particles physics01 natural sciencesMuon captureRenormalizationFormalism (philosophy of mathematics)symbols.namesake0103 physical sciencesQuasiparticlesymbols010306 general physicsWave functionMultipole expansionHamiltonian (quantum mechanics)Physical Review C
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Dissipation and Elliptic Flow at Relativistic Energies

2004

We compare elliptic flow evolution from ideal hydrodynamics and covariant parton transport theory, and show that, for conditions expected at RHIC, dissipation significantly reduces elliptic flow even for extreme parton cross sections and/or densities ${\ensuremath{\sigma}}_{gg}\ifmmode\times\else\texttimes\fi{}dN/d\ensuremath{\eta}(b=0)\ensuremath{\sim}45\text{ }\mathrm{m}\mathrm{b}\ifmmode\times\else\texttimes\fi{}1000$. The difference between transport and hydrodynamic elliptic flow is established rather early during the evolution of the system, but the buildup of elliptic flow is insensitive to the choice of the initial (formation or thermalization) time in both models.

PhysicsParticle physics010308 nuclear & particles physicsElliptic flowGeneral Physics and AstronomySigmaPartonDissipation01 natural sciencesThermalisation0103 physical sciencesQuark–gluon plasmaCovariant transformationIdeal (ring theory)010306 general physicsPhysical Review Letters
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Anomalous Fluctuations of Nematic Order in Solutions of Semiflexible Polymers

2016

The nematic ordering in semiflexible polymers with contour length $L$ exceeding their persistence length $\ell_p$ is described by a confinement of the polymers in a cylinder of radius $r_{eff}$ much larger than the radius $r_\rho$, expected from the respective concentration of the solution. Large scale Molecular Dynamics simulations combined with Density Functional Theory are used to locate the Isotropic-Nematic ($I-N$)-transition and to validate this cylindrical confinement. Anomalous fluctuations, due to chain deflections from neighboring chains in the nematic phase are proposed. Considering deflections as collective excitations in the nematically ordered phase of semiflexible polymers el…

PhysicsPersistence lengthQuantitative Biology::Biomolecules010304 chemical physicsCondensed matter physicsFOS: Physical sciencesGeneral Physics and AstronomyOrder (ring theory)02 engineering and technologyRadiusCondensed Matter - Soft Condensed Matter021001 nanoscience & nanotechnology01 natural sciencesCondensed Matter::Soft Condensed MatterLiquid crystalPhase (matter)0103 physical sciencesQuasiparticleSoft Condensed Matter (cond-mat.soft)CylinderDensity functional theory0210 nano-technologyPhysical Review Letters
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Dissipation-induced coherent structures in Bose-Einstein condensates.

2008

We discuss how to engineer the phase and amplitude of a complex order parameter using localized dissipative perturbations. Our results are applied to generate and control various types of atomic nonlinear matter waves (solitons) by means of localized dissipative defects.

PhysicsPhase (waves)General Physics and AstronomyFOS: Physical sciencesPattern Formation and Solitons (nlin.PS)Dissipation01 natural sciencesNonlinear Sciences - Pattern Formation and Solitons010305 fluids & plasmaslaw.inventionCondensed Matter - Other Condensed MatterNonlinear systemAmplitudelawQuantum mechanics0103 physical sciencesDissipative systemMatter wavePerturbation theory010306 general physicsBose–Einstein condensateOther Condensed Matter (cond-mat.other)Physical review letters
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Soliton rains in a fiber laser: An experimental study

2010

Rains of solitons constitute a class of nonlinear dynamics of dissipative soliton ensembles that we briefly reported in Opt. Express 17, 11776 (2009) from a fiber laser experiment. The existence of a relatively intense noisy background together with several tens of soliton pulses aggregated in a condensed soliton phase constitutes a necessary condition for their appearance. New soliton pulses form spontaneously from the background fluctuations and drift until they reach the condensed soliton phase. We here relate in detail the experimental conditions under which soliton rains manifest and their key features, describe related dynamics observed in their vicinity, and propose an explanation fo…

PhysicsPhase (waves)Key featuresLaserQuasi particlesAtomic and Molecular Physics and Opticslaw.inventionDissipative solitonNonlinear systemNonlinear Sciences::Exactly Solvable and Integrable SystemslawQuantum mechanicsSolitonA fibersNonlinear Sciences::Pattern Formation and SolitonsPhysical Review A
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Effects of heat flux on lambda transition in liquid 4He,

2014

This paper is concerned with the derivation of a phase field model for λ-transition in 4He, when the liquid is subject to pressure and heat flux. As parameter that controls the transition, a field f that is the geometrical mean between the density of the fluid and that of the superfluid is used. The resulting model, that is a generalization of previous papers on the same subject, chooses as field variables the density, the velocity, the temperature and the heat flux, in addition to this field f. The restrictions on the constitutive quantities are obtained by using the Liu method of Lagrange multipliers. New results with respect to previous models are the presence of non-local terms to descr…

PhysicsPhase transitionField (physics)Liquid heliumMechanical EngineeringMechanicsCondensed Matter Physicslaw.inventionSuperfluidityClassical mechanicsHeat fluxMechanics of MaterialslawPhase (matter)ThermalDissipative systemLiquid helium Phase transitions Mean phase-field model Superfluids.Settore MAT/07 - Fisica Matematica
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The Topological Phase Transitions Related to Fermion Condensate

2014

In this chapter, we consider so-called topological phase transitions, taking place in normal Fermi liquid. In other words, here we are dealing with different instabilities of normal Fermi liquids relative to several kinds of perturbations of initial quasiparticle spectrum \(\varepsilon (p)\) and occupation numbers \(n(p)\) associated with the emergence of a multi-connected Fermi surface. Depending on the parameters and analytical properties of the Landau interaction, such instabilities lead to several possible types of restructuring of initial Landau Fermi liquid ground state. This restructuring generates topologically distinct phases. One of them is the FC discussed above, another one belo…

PhysicsPhase transitionPhase (matter)QuasiparticleFermi surfaceFermionFermi liquid theoryGround stateTopologyFermi Gamma-ray Space Telescope
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Noncritical generation of nonclassical frequency combs via spontaneous rotational symmetry breaking

2016

Synchronously pumped optical parametric oscillators (SPOPOs) are optical cavities containing a nonlinear crystal capable of down-converting a frequency comb to lower frequencies. These have received a lot of attention lately, because their intrinsic multimode nature makes them compact sources of quantum correlated light with promising applications in modern quantum information technologies. In this work we show that SPOPOs are also capable of accessing the challenging but interesting regime where spontaneous symmetry breaking plays a crucial role in the quantum properties of the emitted light, difficult to access with any other nonlinear optical cavity. Apart from opening the possibility of…

PhysicsPhase transitionQuantum PhysicsSpontaneous symmetry breakingRotational symmetryFOS: Physical sciencesPhysics::Optics01 natural sciencesÒptica quàntica010309 opticsFrequency combQuantum mechanics0103 physical sciencesDissipative systemNonclassical lightQuantum information010306 general physicsQuantum Physics (quant-ph)QuantumOptics (physics.optics)Physics - Optics
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Optomechanical systems close to the conservative limit

2017

In dissipative optomechanical systems, the total damping hits negative values at the parametric instability point. This also corresponds to the phonon lasing threshold, where the mechanical resonator enters in the self-induced oscillations regime. This paper shows that the two mentioned phenomena are delayed from each other when the optomechanical systems operate close to their conservative limit, where the mechanical damping is very small. In fact, the total damping can be negative and very small for a while before the phonon lasing happens. As a result, the linearized theory is extended over the negative damping region where the mechanical displacements remain very small. It follows that …

PhysicsPhononPhysics::Optics01 natural sciencesParametric instability010309 opticsResonatorNonlinear systemQuantum mechanics0103 physical sciencesLimit (music)Dissipative system010306 general physicsLasing thresholdMultistabilityPhysical Review A
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SNR measurements of silicon photomultipliers in the continuous wave regime

2014

We report on our Signal-to-Noise Ratio (SNR) measurements carried out, in the continuous wave regime, at different frequencies and at various temperatures, on a novel class of silicon photomultipliers (SiPMs) fabricated in planar technology on silicon p-type substrate. SNR of SiPMs is given by the ratio of the photogenerated current, filtered and averaged by a lock-in amplifier, and the Root Mean Square (RMS) deviation of the same current. In our measurements, we have employed a 10 Hz equivalent noise bandwidth, around the lock-in amplifier reference frequency. The measured noise takes into account the shot noise, resulting from the photocurrent and the dark current, while background light …

PhysicsPhotomultiplierPhysics::Instrumentation and Detectorsbusiness.industrysipm photomultiplier snr noise siliconAmplifierShot noiseNoise (electronics)Settore ING-INF/01 - ElettronicaRoot mean squareOpticsSilicon photomultiplierSignal-to-noise ratio (imaging)businessDark current
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