publicationDate
stringlengths
1
2.79k
title
stringlengths
1
36.5k
abstract
stringlengths
1
37.3k
id
stringlengths
9
47
2001-06-05
On Nonlinear Alfvén Waves Generated by Cosmic Ray Streaming Instability
Nonlinear damping of parallel propagating Alfv\'en waves in high-$\beta$ plasma is considered. Trapping of thermal ions and Coulomb collisions are taken into account. Saturated damping rate is calculated. Applications are made for cosmic ray propagation in the Galaxy.
0106078v1
2001-10-15
The UCSD HIRES/KeckI Damped Lya Abundance Database: II. The Implications
We present a comprehensive analysis of the damped Lya abundance database presented in the first paper of this series. This database provides a homogeneous set of abundance measurements for many elements including Si, Cr, Ni, Zn, Fe, Al, S, Co, O, and Ar from 38 damped Lya systems with z > 1.5. With little exception, these damped Llya systems exhibit very similar relative abundances. There is no significant correlation in X/Fe with [Fe/H] metallicity and the dispersion in X/Fe is small at all metallicity. We search the database for trends indicative of dust depletion and in a few cases find strong evidence. Specifically, we identify a correlation between [Si/Ti] and [Zn/Fe] which is unambiguous evidence for depletion. We present a discussion on the nucleosynthetic history of the damped Lya systems by focusing on abundance patterns which are minimally affected by dust depletion. We find [Si/Fe] -> +0.25 dex as [Zn/Fe] -> 0 and that the [Si/Fe] values exhibit a plateau of ~+0.3 dex at [Si/H] < -1.5 dex. Together these trends indicate significant alpha-enrichment in the damped Lya systems at low metallicity, an interpretation further supported by the observed O/Fe, S/Fe and Ar/Fe ratios. We also discuss Fe-peak nucleosynthesis and the odd-even effect. To assess the impact of dust obscuration, we present estimates of the dust-to-gas ratios for the damped Lya sightlines and crudely calculate dust extinction corrections. The distribution of extinction corrections suggests the effects of dust obscuration are minimal and that the population of 'missing' damped systems has physical characteristics similar to the observed sample. We update our investigation on the chemical evolution of the early universe in neutral gas. [significantly abridged]
0110351v1
2005-09-05
Comment on "Damping of Tensor Modes in Cosmology"
We provide an analytic solution to the short wave length limit of the integro-differential equation describing the damping of the tensor modes of gravitational waves.
0509096v2
1997-02-12
Crossover from coherent to incoherent dynamics in damped quantum systems
The destruction of quantum coherence by environmental influences is investigated taking the damped harmonic oscillator and the dissipative two-state system as prototypical examples. It is shown that the location of the coherent-incoherent transition depends to a large degree on the dynamical quantity under consideration.
9702115v1
1998-06-05
Dielectric formalism and damping of collective modes in trapped Bose-Einstein condensed gases
We present the general dielectric formalism for Bose-Einstein condensed systems in external potential at finite temperatures. On the basis of a model arising within this framework as a first approximation in an intermediate temperature region for large condensate we calculate the damping of low-energy excitations in the collisionless regime.
9806079v1
1999-05-27
Do correlations create an energy gap in electronic bilayers? Critical analysis of different approaches
This paper investigates the effect of correlations in electronic bilayers on the longitudinal collective mode structure. We employ the dielectric permeability constructed by means of the classical theory of moments. It is shown that the neglection of damping processes overestimates the role of correlations. We conclude that the correct account of damping processes leads to an absence of an energy gap.
9905405v1
1999-11-16
Damping of low-energy excitations of a Bose-condensed gas in the hydrodynamic regime
We develop a theory to describe the damping of elementary excitations of a Bose-condensed gas in the hydrodynamic regime for the thermal cloud. We discuss second sound in a spatially homogeneous gas and the lowest excitations of a trapped condensate.
9911238v2
2002-04-18
Faraday patterns in Bose-Einstein condensates. Amplitude equation for rolls in the parametrically driven, damped Gross-Pitaevskii equation
The parametrically driven, damped Gross-Pitaevskii equation, which models Bose-Einstein condensates in which the interatomic s-wave scattering length is modulated in time, is shown to support spatially modulated states in the form of rolls. A Landau equation with broken phase symmetry is derived, which governs the dynamics of the roll amplitude.
0204406v1
2002-11-14
Sound damping in ferrofluids: Magnetically enhanced compressional viscosity
The damping of sound waves in magnetized ferrofluids is investigated and shown to be considerably higher than in the non-magnetized case. This fact may be interpreted as a field-enhanced, effective compressional viscosity -- in analogy to the ubiquitous field-enhanced shear viscosity that is known to be the reason for many unusual behavior of ferrofluids under shear.
0211297v1
2003-10-23
Input and output in damped quantum systems III: Formulation of damped systems driven by Fermion fields
A comprehensive input-output theory is developed for Fermionic input fields. Quantum stochastic differential equations are developed in both the Ito and Stratonovich forms. The major technical issue is the development of a formalism which takes account of anticommutation relations between the Fermionic driving field and those system operators which can change the number of Fermions within the system.
0310542v1
2004-01-12
Nonexponential motional damping of impurity atoms in Bose-Einstein condensates
We demonstrate that the damping of the motion of an impurity atom injected at a supercritical velocity into a Bose-Einstein condensate can exhibit appreciable deviation from the exponential law on time scales of $10^{-5}$ s.
0401172v1
2005-02-21
Two Transitions in the Damping of a Unitary Fermi Gas
We measure the temperature dependence of the radial breathing mode in an optically trapped, strongly-interacting Fermi gas of $^6$Li, just above the center of a broad Feshbach resonance. The frequency remains close to the unitary hydrodynamic value, while the damping rate reveals transitions at two well-separated temperatures, consistent with the existence of atom pairs above a superfluid transition.
0502507v1
1994-07-04
Cat States and Single Runs for the Damped Harmonic Oscillator
We discuss the fate of initial states of the cat type for the damped harmonic oscillator, mostly employing a linear version of the stochastic Schr\"odinger equation. We also comment on how such cat states might be prepared and on the relation of single realizations of the noise to single runs of experiments.
9407001v1
2000-10-27
Damping and the Hartree Ensemble Approximation
We study a Hartree ensemble approximation for real-time dynamics in the toy model of 1+1 dimensional scalar field theory. Damping behavior seen in numerical simulations is compared with analytical predictions based on perturbation theory in the original (non-Hartree-approximated) model.
0010054v1
1995-03-21
APPLICATIONS OF HIGH-TEMPERATURE FIELD THEORY TO HEAVY-ION COLLISIONS
A recent development in finite temperature field theory, the so-called Braaten-Pisarski method, and its application to properties of a quark-gluon plasma, possibly formed in relativistic heavy ion collisions, are reviewed. In particular parton damping rates, the energy loss of energetic partons, thermalization times, viscosity, and production and damping rates of hard photons are discussed.
9503400v1
1996-03-19
Damping Rate and Lyapunov Exponent of a Higgs Field at High Temperature
The damping rate of a Higgs field at zero momentum is calculated using the Braaten-Pisarski method and compared to the Lyapunov exponent of the classical SU(2) Yang-Mills Higgs system.
9603339v1
1997-04-30
Comments on the Erhan-Schlein model of damping the pomeron flux at small x-pomeron
We explore the theoretical and experimental consequences of a model proposed by Samim Erhan and Peter Schlein for unitarizing the diffractive amplitude by damping the pomeron flux at small x-pomeron and conclude that the model is unphysical and contradicts well established experimental data.
9704454v1
1998-03-26
The Nonlinear Spatial Damping Rate in QGP
The derivative expansion method has been used to solve the semiclassical kinetic equations of quark-gluon plasma (QGP). The nonlinear spatial damping rate, the imaginary part of the wave vector, for the longitudinal secondary color waves in the long wavelength limit has been calculated numerically.
9803455v1
2006-07-27
Long-Time Asymptotic Behavior of Dissipative Boussinesq System
In this paper, we study various dissipative mechanics associated with the Boussinesq systems which model two-dimensional small amplitude long wavelength water waves. We will show that the decay rate for the damped one-directional model equations, such as the KdV and BBM equations, holds for some of the damped Boussinesq systems which model two-directional waves.
0607708v1
2006-12-27
Stochastic inertial manifolds for damped wave equations
In this paper, stochastic inertial manifold for damped wave equations subjected to additive white noise is constructed by the Lyapunov-Perron method. It is proved that when the intensity of noise tends to zero the stochastic inertial manifold converges to its deterministic counterpart almost surely.
0612774v1
2007-01-19
On the Domain of Analyticity and Small Scales for the Solutions of the Damped-driven 2D Navier-Stokes Equations
We obtain a logarithmically sharp estimate for the space-analyticity radius of the solutions of the damped-driven 2D Navier-Stokes equations with periodic boundary conditions and relate this to the small scales in this system. This system is inspired by the Stommel--Charney barotropic ocean circulation model.
0701530v1
2002-09-04
Wigner function for damped systems
Both classical and quantum damped systems give rise to complex spectra and corresponding resonant states. We investigate how resonant states, which do not belong to the Hilbert space, fit the phase space formulation of quantum mechanics. It turns out that one may construct out of a pair of resonant states an analog of the stationary Wigner function.
0209008v1
2004-12-14
Two-Ion Dusty Plasma Waves and Landau Damping
The paper analyses the properties of dusty plasmas in the extreme conditions when the free electrons are absent. The nonlinear Korteveg de Vries equation with a nonlocal (integral) term in a small parameter approximation is derived. The conditions are determined when the integral term is essential hence the Landau damping of two-ion-dusty plasma waves is substantial.
0412033v1
2002-10-16
Dependence of Nuclear Level Density on Vibrational State Damping
The response function approach is proposed to include vibrational state in calculation of level density. The calculations show rather strong dependence of level density on the relaxation times of collective state damping.
0210048v1
1999-02-09
One-Dimensional Motion of Sommerfeld Sphere in Potential Hole in Classical Electrodynamics: Inside the Hole
Equation of motion of Sommerfeld sphere in the one-dimensional potential hole, produced by two equal charges on some distance from each other, is numerically investigated. Two types of solutions are found: (i) damping oscillations, (ii) oscillations without damping (radiationless motion). Solutions with growing amplitude ("climbing-up-the-wall solution") for chosen initial conditions were not founded.
9902018v3
2000-03-23
The Hawking-Unruh Temperature and Damping in a Linear Focusing Channel
The Hawking-Unruh effective temperature, hbar a* / 2 pi c k, due to quantum fluctuations in the radiation of an accelerated charged-particle beam can be used to show that transverse oscillations of the beam in a practical linear focusing channel damp to the quantum-mechanical limit. A comparison is made between this behavior and that of beams in a wiggler.
0003061v1
2003-06-17
Ruchhardt Oscillator Decay- Thermodynamic basis for Hysteretic Damping
Using thermodynamic arguments based on the ideal gas law, it is shown that hysteretic (also called structural) damping is the natural form of energy dissipation for this classic oscillator that is used to measure the ratio of heat capacities for a gas.
0306136v1
2005-08-25
Rutherford scattering with radiation damping
We study the effect of radiation damping on the classical scattering of charged particles. Using a perturbation method based on the Runge-Lenz vector, we calculate radiative corrections to the Rutherford cross section, and the corresponding energy and angular momentum losses.
0508186v2
2006-01-18
Expressions for frictional and conservative force combinations within the dissipative Lagrange-Hamilton formalism
Dissipative Lagrangians and Hamiltonians having Coulomb, viscous and quadratic damping,together with gravitational and elastic terms are presented for a formalism that preserves the Hamiltonian as a constant of the motion. Their derivations are also shown. The resulting L's and H's may prove useful in exploring new types of damped quantum systems.
0601133v1
1997-03-27
Macroscopic quantum damping in SQUID rings
The measurement process is introduced in the dynamics of Josephson devices exhibiting quantum behaviour in a macroscopic degree of freedom. The measurement is shown to give rise to a dynamical damping mechanism whose experimental observability could be relevant to understand decoherence in macroscopic quantum systems.
9703052v1
2005-07-19
Radiation reaction and quantum damped harmonic oscillator
By taking a Klein-Gordon field as the environment of an harmonic oscillator and using a new method for dealing with quantum dissipative systems (minimal coupling method), the quantum dynamics and radiation reaction for a quantum damped harmonic oscillator investigated. Applying perturbation method, some transition probabilities indicating the way energy flows between oscillator, reservoir and quantum vacuum, obtained
0507179v1
2005-08-18
Density operator and entropy of the damped quantum harmonic oscillator
The expression for the density operator of the damped harmonic oscillator is derived from the master equation in the framework of the Lindblad theory for open quantum systems. Then the von Neumann entropy and effective temperature of the system are obtained. The entropy for a state characterized by a Wigner distribution function which is Gaussian in form is found to depend only on the variance of the distribution function.
0508141v1
2006-03-03
On the damping of the angular momentum of three harmonic oscillators
In the frame of the Lindblad theory of open quantum systems, the system of three uncoupled harmonic oscillators with opening operators linear in the coordinates and momenta of the considered system is analyzed. The damping of the angular momentum and of its projection is obtained.
0603029v1
2006-10-10
Simultaneous amplification and non-symmetric amplitude damping of two-mode Gaussian state
The evolution of two-mode Gaussian state under symmetric amplification, non-symmetric damping and thermal noise is studied. The time dependent solution of the state characteristic function is obtained. The separability criterions are given for the final state of weak amplification as well as strong amplification.
0610070v1
2007-10-13
The separability of tripartite Gaussian state with amplification and amplitude damping
Tripartite three mode Gaussian state undergoes parametric amplification and amplitude damping as well as thermal noise is studied. In the case of a state totally symmetrically interacting with the environment, the time dependent correlation matrix of the state in evolution is given. The conditions for fully separability and fully entanglement of the final tripartite three mode Gaussian state are worked out.
0710.2570v1
2007-12-16
Nonadditive quantum error correcting codes adapted to the ampltitude damping channel
A family of high rate quantum error correcting codes adapted to the amplitude damping channel is presented. These codes are nonadditive and exploit self-complementarity structure to correct all first-order errors. Their rates can be higher than 1/2. The recovery operations of these codes can be generated by a simple algorithm and have a projection nature, which makes them potentially easy to implement.
0712.2586v1
2007-12-22
Chaos in an intermittently driven damped oscillator
We observe chaotic dynamics in a damped linear oscillator, which is driven only at certain regions of phase space. Both deterministic and random drives are studied. The dynamics is characterized using standard techniques of nonlinear dynamics. Interchanging roles of determinism and stochasticity is also considered.
0712.3827v2
2008-03-01
Well-posedness of the IBVP for 2-D Euler Equations with Damping
In this paper we focus on the initial-boundary value problem of the 2-D isentropic Euler equations with damping. We prove the global-in-time existence of classical solution to the initial-boundary value problem by the method of energy estimates.
0803.0039v1
2008-03-27
Shear viscosity of degenerate electron matter
We calculate the partial electron shear viscosity $\eta_{ee}$ limited by electron-electron collisions in a strongly degenerate electron gas taking into account the Landau damping of transverse plasmons. The Landau damping strongly suppresses $\eta_{ee}$ in the domain of ultrarelativistic degenerate electrons and modifies its %asymptotic temperature behavior. The efficiency of the electron shear viscosity in the cores of white dwarfs and envelopes of neutron stars is analyzed.
0803.3893v1
2008-04-09
Stationary Oscillations in a Damped Wave Equation from Isospectral Bessel Functions
Using the isospectral partners of the Bessel functions derived by Reyes et al., we find, on one hand, that these functions show non-typical supersymmetric (SUSY) behavior and, on the other, that the isospectral partner of the classical wave equation is equivalent to that of a damped system whose oscillations do not vanish in time, but show a non-harmonic shape.
0804.1510v1
2008-06-03
Simulation study of fast ion instability in the ILC damping ring and PETRA III
The fast ion instability is simulated in different gas pressures and fill patterns for the damping ring of the International Linear Collider (ILC) and PETRA III respectively. Beam size variation due to beta function and dispersion function change is taken into account. Feedback is also applied in the simulation.
0806.0529v1
2008-08-01
Damped wave equations with dynamic boundary conditions
We discuss several classes of linear second order initial-boundary value problems, where damping terms appear in the main wave equation as well as in the dynamic boundary condition. We investigate their well-posedness and describe some qualitative properties of their solutions, including boundedness, stability, or almost periodicity. In particular, we are able to characterize the analyticity of certain $C_0$-semigroups associated to such problems. Applications to several problems on domains and networks are shown.
0808.0213v1
2008-12-17
The damping of gravitational waves in dust
We examine a simple model of interaction of gravitational waves with matter (primarily represented by dust). The aim is to investigate a possible damping effect on the intensity of gravitational wave when passing through media. This might be important for gravitational wave astronomy when the sources are obscured by dust or molecular clouds.
0812.3336v1
2009-05-24
Computer assisted proof of the existence of homoclinic tangency for the Henon map and for the forced-damped pendulum
We present a topological method for the efficient computer assisted verification of the existence of the homoclinic tangency which unfolds generically in a one-parameter family of planar maps. The method has been applied to the Henon map and the forced damped pendulum ODE.
0905.3924v1
2009-08-15
Antigravitation, Dark Energy, Dark Matter - Alternative Solution
Collisional damping of gravitational waves in the Newtonian matter is investigated. The generalized theory of Landau damping is applied to the gravitational physical systems in the context of the plasma gravitational analogy.
0908.2180v3
2009-08-31
A comment about the existence of a weak solution for a non linear wave equation damped propagation
We give a proof for the existence of a weak solution on the initial-value problem of a non-linear damped propagation
0909.0052v2
2009-09-15
Quantum Parrondo's games under decoherence
We study the effect of quantum noise on history dependent quantum Parrondo's games by taking into account different noise channels. Our calculations show that entanglement can play a crucial role in quantum Parrondo's games. It is seen that for the maximally entangled initial state in the presence of decoherence, the quantum phases strongly influence the payoffs for various sequences of the game. The effect of amplitude damping channel leads to winning payoffs. Whereas the depolarizing and phase damping channels lead to the losing payoffs. In case of amplitude damping channel, the payoffs are enhanced in the presence of decoherence for the sequence AAB. This is because the quantum phases interfere constructively which leads to the quantum enhancement of the payoffs in comparison to the undecohered case. It is also seen that the quantum phase angles damp the payoffs significantly in the presence of decoherence. Furthermore, it is seen that for multiple games of sequence AAB, under the influence of amplitude damping channel, the game still remains a winning game. However, the quantum enhancement reduces in comparison to the single game of sequence AAB because of the destructive interference of phase dependent terms. In case of depolarizing channel, the game becomes a loosing game. It is seen that for the game sequence B the game is loosing one and the behavior of sequences B and BB is similar for amplitude damping and depolarizing channels. In addition, the repeated games of A are only influenced by the amplitude damping channel and the game remains a losing game. Furthermore, it is also seen that for any sequence when played in series, the phase damping channel does not influence the game.
0909.2897v2
2009-10-01
Global attractor for weakly damped Nonlinear Schrödinger equations in $L^2(\R)$
We prove that the weakly damped nonlinear Schr\"odinger flow in $L^2(\mathbb{R})$ provides a dynamical system which possesses a global attractor. The proof relies on the continuity of the Schr\"odinger flow for the weak topology in $L^2(\R)$.
0910.0172v1
2009-12-11
Waves, damped wave and observation
We consider the wave equation in a bounded domain (eventually convex). Two kinds of inequality are described when occurs trapped ray. Applications to control theory are given. First, we link such kind of estimate with the damped wave equation and its decay rate. Next, we describe the design of an approximate control function by an iterative time reversal method.
0912.2202v1
2010-01-01
Exponential Energy Decay for Damped Klein-Gordon Equation with Nonlinearities of Arbitrary Growth
We derive a uniform exponential decay of the total energy for the nonlinear Klein-Gordon equation with a damping around spatial infinity in the whole space or in the exterior of a star shaped obstacle.
1001.0209v1
2010-03-10
Covariant Constitutive Relations, Landau Damping and Non-stationary Inhomogeneous Plasmas
Models of covariant linear electromagnetic constitutive relations are formulated that have wide applicability to the computation of susceptibility tensors for dispersive and inhomogeneous media. A perturbative framework is used to derive a linear constitutive relation for a globally neutral plasma enabling one to describe in this context a generalized Landau damping mechanism for non-stationary inhomogeneous plasma states.
1003.2062v1
2010-03-28
Damped wave dynamics for a complex Ginzburg-Landau equation with low dissipation
We consider a complex Ginzburg-Landau equation, corresponding to a Gross-Pitaevskii equation with a small dissipation term. We study an asymptotic regime for long-wave perturbations of constant maps of modulus one. We show that such solutions never vanish and we derive a damped wave dynamics for the perturbation.
1003.5375v1
2010-06-16
Hysteresis effects in Bose-Einstein condensates
Here, we consider damped two-components Bose-Einstein condensates with many-body interactions. We show that, when the external trapping potential has a double-well shape and when the nonlinear coupling factors are modulated in time, hysteresis effects may appear under some circumstances. Such hysteresis phenomena are a result of the joint contribution between the appearance of saddle node bifurcations and damping effect.
1006.3240v1
2010-09-25
Different Network Topologies for Distributed Electric Damping of Beam Vibrations
In this work passive electric damping of structural vibrations by distributed piezoelectric transducers and electric networks is analyzed. Different distributed electric controllers are examined as finite degrees of freedom systems and their performances are compared. Modal reduction is used to optimize the electric parameters
1009.5001v1
2010-12-27
The Relativistic kinetics of gravitational waves collisional damping in hot Universe
The article is a translation of authors paper printed earlier in the inaccessible edition and summarizing the results of research of gravitational waves damping problem in the cosmologic plasma due to the different interactions of elementary particles.
1012.5582v1
2011-01-14
Blowup for the Damped $L^{2}$-Critical Nonlinear Schrödinger Equation
We consider the Cauchy problem for the $L^{2}$-critical damped nonlinear Schr\"odinger equation. We prove existence and stability of finite time blowup dynamics with the log-log blow-up speed for $\|\nabla u(t)\|_{L^2}$.
1101.2763v3
2011-02-05
Partial regularity of weak solutions of the viscoelastic Navier-Stokes equations with damping
We prove an analog of the Caffarelli-Kohn-Nirenberg theorem for weak solutions of a system of PDE that model a viscoelastic fluid in the presence of an energy damping mechanism. The system was recently introduced as a possible method of establishing the global in time existence of weak solutions of the well known Oldroyd system.
1102.1112v1
2011-02-21
The One Dimensional Damped Forced Harmonic Oscillator Revisited
In this paper we give a general solution to the problem of the damped harmonic oscillator under the influence of an arbitrary time-dependent external force. We employ simple methods accessible for beginners and useful for undergraduate students and professors in an introductory course of mechanics.
1102.4112v1
2011-03-18
Soliton complexity in the damped-driven nonlinear Schrödinger equation: stationary, periodic, quasiperiodic complexes
Stationary and oscillatory bound states, or complexes, of the damped-driven solitons are numerically path-followed in the parameter space. We compile a chart of the two-soliton attractors, complementing the one-soliton attractor chart.
1103.3607v1
2011-09-27
Exponential energy decay of solutions for a system of viscoelastic wave equations of Kirchhoff type with strong damping
The initial boundary value problem for a system of viscoelastic wave equations of Kirchhoff type with strong damping is considered. We prove that, under suitable assumptions on relaxation functions and certain initial data, the decay rate of the solutions energy is exponential.
1109.5921v1
2011-11-20
Null controllability of the structurally damped wave equation with moving point control
We investigate the internal controllability of the wave equation with structural damping on the one dimensional torus. We assume that the control is acting on a moving point or on a moving small interval with a constant velocity. We prove that the null controllability holds in some suitable Sobolev space and after a fixed positive time independent of the initial conditions.
1111.4655v1
2011-12-04
On the Apparent Superluminal Motion of a Damped Gaussian Pulse
Alicki has demonstrated that a travelling Gaussian pulse subject to damping is indistinguishable from an undamped pulse moving with greater speed; such an effect could create the illusion of a pulse moving faster than light. In this note, an alternative derivation of the same result is presented. However, it is unlikely that this particular illusion could explain the superluminal neutrino-velocities reported by OPERA.
1112.1324v1
2011-12-28
Photon Damping in One-Loop HTL Perturbation Theory
We determine the damping rates of slow-moving photons in next-to-leading order hard-thermal-loop perturbation of massless QED. We find both longitudinal and transverse rates finite, positive, and equal at zero momentum. Various divergences, light-cone and at specific momenta, but not infrared, appear and cancel systematically.
1112.6065v2
2012-04-06
Late time evolution of the gravitational wave damping in the early Universe
An analytical solution for time evolution of the gravitational wave damping in the early Universe due to freely streaming neutrinos is found in the late time regime. The solution is represented by a convergent series of spherical Bessel functions of even order and was possible with the help of a new compact formula for the convolution of spherical Bessel functions of integer order.
1204.1384v2
2012-05-30
Beam Dynamics Studies for the CLIC Main Linac
The implications of long-range wakefields on the beam quality are investigated through a detailed beam dynamics study. Injection offsets are considered and the resulting emittance dilution recorded, including systematic sources of error. These simulations have been conducted for damped and detuned structures (DDS) and for waveguide damped structures-both for the CLIC collider.
1205.6623v2
2012-07-31
Energy decay rates for solutions of the wave equations with nonlinear damping in exterior domain
In this paper we study the behaviors of the energy of solutions of the wave equations with localized nonlinear damping in exterior domains.
1207.7336v3
2012-11-02
A modified test function method for damped waves
In this paper we use a modified test function method to derive nonexistence results for the semilinear wave equation with time-dependent speed and damping. The obtained critical exponent is the same exponent of some recent results on global existence of small data solution.
1211.0453v1
2012-12-15
Damping and Pseudo-fermions
After a short abstract introduction on the time evolution driven by non self-adjoint hamiltonians, we show how the recently introduced concept of {\em pseudo-fermion} can be used in the description of damping in finite dimensional quantum systems, and we compare the results deduced adopting the Schr\"odinger and the Heisenberg representations.
1212.3663v1
2013-01-14
On estimating the output entropy of a tensor product of the quantum phase-damping channel with an arbitrary channel
We obtained the estimation from below for the output entropy of a tensor product of the quantum phase-damping channel with an arbitrary channel. It is shown that from this estimation immediately follows that the strong superadditivity of the output entropy holds for this channel as well as for the quantum depolarizing channel.
1301.2886v1
2013-06-10
Smooth attractors for the quintic wave equations with fractional damping
Dissipative wave equations with critical quintic nonlinearity and damping term involving the fractional Laplacian are considered. The additional regularity of energy solutions is established by constructing the new Lyapunov-type functional and based on this, the global well-posedness and dissipativity of the energy solutions as well as the existence of a smooth global and exponential attractors of finite Hausdorff and fractal dimension is verified.
1306.2294v1
2013-07-20
Entanglement-assisted capacities of time-correlated amplitude-damping channel
We calculate the information capacities of a time-correlated amplitude-damping channel, provided the sender and receiver share prior entanglement. Our analytical results show that the noisy channel with zero capacity can transmit information if it has finite memory. The capacities increase as the memory increases attaining maximum value for perfect memory channel.
1307.5403v1
2013-07-23
Comment on Damping Force in the Transit-time Method of Optical Stochastic Cooling
In this brief report we pointed at mistake in paper A. Zholents, Damping Force in the Transit-Time Method of Optical Stochastic Cooling, PRLST. Mar 1, 2012. 2 pp. Published in Phys.Rev.ST Accel. Beams 15 (2012) 032801.
1307.6185v1
2013-08-23
Stability results for second-order evolution equations with switching time-delay
We consider second-order evolution equations in an abstract setting with intermittently delayed/ not-delayed damping. We give sufficient conditions for asymptotic and exponential stability, improving and generalising our previous results from [19]. In particular, under suitable conditions, we can consider unbounded damping operators. Some concrete examples are finally presented.
1308.5100v1
2013-09-10
Convergence of global solutions for some classes of nonlinear damped wave equations
We consider the asymptotic behavior of the soltion to the wave equation with time-dependent damping and analytic nonlinearity. Our main goal is to prove the convergence of a global solution to an equilibrium as time goes to infinity by means of a suitable Lojasiewicz-Simon type inequality.
1309.2364v1
2013-09-13
On diffusion phenomena for the linear wave equation with space-dependent damping
In this paper, we prove the diffusion phenomenon for the linear wave equation with space-dependent damping. We prove that the asymptotic profile of the solution is given by a solution of the corresponding heat equation in the $L^2$-sense.
1309.3377v1
2013-09-19
Compressible Euler equation with damping on Torus in arbitrary dimensions
We study the exponential stability of constant steady state of isentropic compressible Euler equation with damping on $\mathbb T^n$. The local existence of solutions is based on semigroup theory and some commutator estimates. We propose a new method instead of energy estimates to study the stability, which works equally well for any spatial dimensions.
1309.5059v3
2013-10-28
Large deviations for a damped telegraph process
In this paper we consider a slight generalization of the damped telegraph process in Di Crescenzo and Martinucci (2010). We prove a large deviation principle for this process and an asymptotic result for its level crossing probabilities (as the level goes to infinity). Finally we compare our results with the analogous well-known results for the standard telegraph process.
1310.7332v1
2013-10-29
Blow-up for the wave equation with nonlinear source and boundary damping terms
The paper deals with blow--up for the solutions of wave equation with nonlinear source and nonlinear boudary damping terms, posed in a bounded and regular domain. The initial data are posed in the energy space. The aim of the paper is to improve previous blow-up results concerning the problem.
1310.7734v1
2013-11-24
Global small solution to the 2D MHD system with a velocity damping term
This paper studies the global well-posedness of the incompressible magnetohydrodynamic (MHD) system with a velocity damping term. We establish the global existence and uniqueness of smooth solutions when the initial data is close to an equilibrium state. In addition, explicit large-time decay rates for various Sobolev norms of the solutions are also given.
1311.6185v1
2014-08-25
Asymptotic behavior of global entropy solutions for nonstrictly hyperbolic systems with linear damping
In this paper we investigate the large time behavior of the global weak entropy solutions to the symmetric Keyftiz-Kranzer system with linear damping. It is proved that as t tends to infinite the entropy solutions tend to zero in the L p norm
1408.5856v1
2014-08-26
Stability of an abstract-wave equation with delay and a Kelvin-Voigt damping
In this paper we consider a stabilization problem for the abstract-wave equation with delay. We prove an exponential stability result for appropriate damping coefficient. The proof of the main result is based on a frequency-domain approach.
1408.6261v2
2015-02-02
Spontaneous toroidal rotation, anomalous radial particle flux, and the electron-ion asymmetric anomalous viscous damping
AA spontaneous toroidal rotation due to the electron-ion asymmetric anomalous viscous damping and the turbulent radial particle flux has been found, which explains the experimental observation of the anomalous toroidal momentum source in the edge of a tokamak plasma.
1502.00499v3
2015-03-06
Concentration Of Laplace Eigenfunctions And Stabilization Of Weakly Damped Wave Equation
- In this article, we prove some universal bounds on the speed of concentration on small (frequency-dependent) neighborhoods of submanifolds of L 2-norms of quasi modes for Laplace operators on compact manifolds. We deduce new results on the rate of decay of weakly damped wave equations. R{\'e}sum{\'e}.
1503.02058v1
2015-03-11
Upper bounds for the attractor dimension of damped Navier-Stokes equations in $\mathbb R^2$
We consider finite energy solutions for the damped and driven two-dimensional Navier--Stokes equations in the plane and show that the corresponding dynamical system possesses a global attractor. We obtain upper bounds for its fractal dimension when the forcing term belongs to the whole scale of homogeneous Sobolev spaces from -1 to 1
1503.03415v1
2015-03-18
Laplace Eigenfunctions And Damped Wave Equation Ii: Product Manifolds
- The purpose of this article is to study possible concentrations of eigenfunc-tions of Laplace operators (or more generally quasi-modes) on product manifolds. We show that the approach of the first author and Zworski [10, 11] applies (modulo rescalling) and deduce new stabilization results for weakly damped wave equations which extend to product manifolds previous results by Leautaud-Lerner [12] obtained for products of tori.
1503.05513v1
2015-10-14
The General Solution to Vlasov Equation and Linear Landau Damping
A general solution to linearized Vlasov equation for an electron electrostatic wave in a homogeneous unmagnetized plasma is derived. The quasi-linear diffusion coefficient resulting from this solution is a continuous function of omega in contrast to that derived from the traditional Vlasov treatment. The general solution is also equivalent to the Landau treatment of the plasma normal oscillations, and hence leads to the well-known Landau damping.
1510.03949v1
2016-01-13
Non uniform decay of the energy of some dissipative evolution systems
In this paper we consider second order evolution equations with bounded damping. We give a characterization of a non uniform decay for the damped problem using a kind of observability estimate for the associated undamped problem.
1601.03373v1
2016-01-27
Forward self-similar solutions to the viscoelastic Navier-Stokes equation with damping
Motivated by \cite{JS}, we prove that there exists a global, forward self-similar solution to the viscoelastic Navier-Stokes equation with damping, that is smooth for $t>0$, for any initial data that is homogeneous of degree $-1$.
1601.07478v1
2016-03-14
Phase speed and frequency-dependent damping of longitudinal intensity oscillations in coronal loop structures observed with AIA/SDO
Longitudinal intensity oscillations along coronal loops that are interpreted as signatures of magneto-acoustic waves are observed frequently in different coronal structures. The aim of this paper is to estimate the physical parameters of the slow waves and the quantitative dependence of these parameters on their frequencies in the solar corona loops that are situated above active regions with the Atmospheric Imaging Assembly (AIA) onboard Solar Dynamic Observatory (SDO). The observed data on 2012-Feb-12, consisting of 300 images with an interval of 24 seconds in the 171 $\rm{\AA}$ and 193 $\rm{\AA}$ passbands is analyzed for evidence of propagating features as slow waves along the loop structures. Signatures of longitudinal intensity oscillations that are damped rapidly as they travel along the loop structures were found, with periods in the range of a few minutes to few tens of minutes. Also, the projected (apparent) phase speeds, projected damping lengths, damping times and damping qualities of filtered intensities centred on the dominant frequencies are measured in the range of $\rm{C_s}\simeq 38-79~ \rm {km~s^{-1}}$, $\rm{L_d}\simeq 23-68 ~\rm{Mm }$, $\rm{\tau_d}\simeq 7- 21 ~\rm {min}$ and $\rm{\tau_d/P}\simeq 0.34- 0.77$, respectively. The theoretical and observational results of this study indicate that the damping times and damping lengths increase with increasing the oscillation periods, and are highly sensitive function of oscillation period, but the projected speeds and the damping qualities are not very sensitive to the oscillation periods. Furthermore, the magnitude values of physical parameters are in good agreement with the prediction of the theoretical dispersion relations of high-frequency MHD waves ($>1.1~ \rm{mHz}$) in a coronal plasma with electron number density in the range of $\rm{n_e}\simeq 10^{7} - 10^{12} ~\rm{cm^{-3}}$.
1603.04207v1
2016-04-27
Critical exponent for nonlinear wave equations with frictional and viscoelastic damping terms
In this paper, we study the Cauchy problem for a nonlinear wave equation with frictional and viscoelastic damping terms. Our aim is to obtain the threshold, to classify the global existence of solution for small data or the finite time blow-up pf the solution, with respect to the growth order of the nonlinearity.
1604.08265v1
2016-05-19
On circular flows: linear stability and damping
In this article we establish linear inviscid damping with optimal decay rates around 2D Taylor-Couette flow and similar monotone flows in an annular domain $B_{r_{2}}(0) \setminus B_{r_{1}}(0) \subset \mathbb{R}^{2}$. Following recent results by Wei, Zhang and Zhao, we establish stability in weighted norms, which allow for a singularity formation at the boundary, and additional provide a description of the blow-up behavior.
1605.05959v1
2016-08-04
Resonance Damping of the THz-frequency Transverse Acoustic Phonon in the Relaxor Ferroelectric KTa1-xNbxO3
The damping ($\Gamma_a$) of the transverse acoustic (TA) phonon in single crystals of the relaxor $KTa_{1-x}Nb_xO_3$ with x=0.15-0.17 was studied by means of high resolution inelastic cold neutron scattering near the (200) B.Z. point where diffuse scattering is absent, although it is present near (110). In a wide range of temperatures centered on the phase transition, T=195K-108K, the TA phonon width (damping) exhibits a step increase around momentum q=0.07, goes through a shallow maximum at q=0.09-0.12 and remains high up to the highest momentum studied of q=0.16. These experimental results are explained in terms of a resonant interaction between the TA phonon and the collective or correlated reorientation through tunneling of the off-center Nb+5 ions. The observed TA damping is successfully reproduced in a simple model that includes an interaction between the TA phonon and a dispersionless localized mode (LM) with frequency $\omega_L$ and damping $\Gamma_L$ ($\Gamma_L < \omega_L$), itself coupled to the transverse optic (TO) mode. Maximum damping of the TA phonon occurs when its frequency $\omega_a \approx{\omega_L}$. $\omega_L$ and $\Gamma_L$ are moderately dependent on temperature but the oscillator strength, $M_2$, of the resonant damping exhibits a strong maximum in the range $T\sim{150 K-120 K}$ in which neutron diffuse scattering near the (110) B.Z. point is also maximum and the dielectric susceptibility exhibits the relaxor behavior. The maximum value of M appears to be due to the increasing number of polar nanodomains. In support of the proposed model, the observed value of $\omega_L$ is found to be similar to the estimate previously obtained by Girshberg and Yacoby. Alternatively, the TA phonon damping can be successfully fitted in the framework of an empirical Havriliak - Negami (HN) relaxation model that includes a strong resonance-like transient contribution.
1608.01591v1
2016-08-26
Cheillini integrability and quadratically damped oscillators
In this paper a new approach to study an equation of the Lienard type with a strong quadratic damping is proposed based on Jacobi's last multiplier and Cheillini's integrability condition. We obtain a closed form solution of the transcendental characteristic equation of the Lienard type equation using the Lambert W-function.
1608.07377v1
2016-11-27
Nonlinear Wave Equation with Damping: Periodic Forcing and Non-Resonant Solutions to the Kuznetsov Equation
Existence of non-resonant solutions of time-periodic type are established for the Kuznetsov equation with a periodic forcing term. The equation is considered in a three-dimensional whole-space, half-space and bounded domain, and with both non-homogeneous Dirichlet and Neumann boundary values. A method based on Lp estimates of the corresponding linearization, namely the wave equation with Kelvin-Voigt damping, is employed.
1611.08883v1
2017-02-02
Stationary solutions for stochastic damped Navier-Stokes equations in $\mathbb R^d$
We consider the stochastic damped Navier-Stokes equations in $\mathbb R^d$ ($d=2,3$), assuming as in our previous work [4] that the covariance of the noise is not too regular, so It\^o calculus cannot be applied in the space of finite energy vector fields. We prove the existence of an invariant measure when $d=2$ and of a stationary solution when $d=3$.
1702.00697v1
2017-03-08
Moderate deviations for the Langevin equation with strong damping
In this paper, we establish a moderate deviations principle for the Langevin dynamics with strong damping. The weak convergence approach plays an important role in the proof.
1703.03033v3
2017-03-17
Damping in a Superconducting Mechanical Resonator
We study a mechanical resonator made of aluminum near the normal to super conductivity phase transition. A sharp drop in the rate of mechanical damping is observed below the critical temperature. The experimental results are compared with predictions based on the Bardeen Cooper Schrieffer theory of superconductivity and a fair agreement is obtained.
1703.05912v1
2017-03-27
On the $L^{2}$-critical nonlinear Schrodinger equation with an inhomogeneous damping term
We consider the $L^2$-critical nonlinear Schrodinger equation with an inhomogeneous damping term. We prove that there exists an initial data such that the corresponding solution is global in $H^1(R^d)$ and we give the minimal time of the blow up for some initial data.
1703.09101v1
2017-06-22
Asymptotic profile of solutions for some wave equations with very strong structural damping
We consider the Cauchy problem in R^n for some types of damped wave equations. We derive asymptotic profiles of solutions with weighted L^{1,1}(R^n) initial data by employing a simple method introduced by the first author. The obtained results will include regularity loss type estimates, which are essentially new in this kind of equations.
1706.07174v1
2017-08-11
Global existence of a diffusion limit with damping for the compressible radiative Euler system coupled to an electromagnetic field
We study the Cauchy problem for a system of equations corresponding to a singular limit of radiative hydrodynamics, namely the 3D radiative compressible Euler system coupled to an electromagnetic field through the MHD approximation. Assuming the presence of damping together with suitable smallness hypotheses for the data, we prove that this problem admits a unique global smooth solution.
1708.03681v1