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47
2016-12-07
Ab initio quantum-statistical approach to kinetic theory of low-temperature dilute gases of hydrogen-like atoms
We develop a microscopic approach to the consistent construction of the kinetic theory of dilute weakly ionized gases of hydrogen-like atoms. The approach is based on the framework of the second quantization method in the presence of bound states of particles and the method of reduced description of relaxation processe...
1612.02245v1
2018-07-27
Phase spreading and temporal coherence of a pair-condensed Fermi gas at low temperature
A condensate of pairs in an isolated, homogeneous, unpolarised, finite-size spin 1/2 Fermi gas at low nonzero temperature T, undergoes with time a phase change with a random component, due to coupling to the gas thermal phonons. With the quantum second Josephson relation relating the derivative of the condensate phase ...
1807.10476v2
2019-08-14
Comparison of wave-structure interaction dynamics of a submerged cylindrical point absorber with three degrees of freedom using potential flow and computational fluid dynamics models
In this paper we compare the heave, surge, and pitch dynamics of a submerged cylindrical point absorber, simulated using potential flow and fully-resolved computational fluid dynamics (CFD) models. The potential flow model is based on the time-domain Cummins equation, whereas the CFD model uses the fictitious domain Br...
1908.04981v4
2019-09-13
Multi-Particle Collisions in Microgravity: Coefficient of Restitution and Sticking Threshold for Systems of Mm-Sized Particles
The current model of planet formation lacks a good understanding of the growth of dust particles inside the protoplanetary disk beyond mm sizes. In order to investigate the low-velocity collisions between this type of particles, the NanoRocks experiment was flown on the International Space Station (ISS) between Septemb...
1909.06417v1
2020-03-20
A comparison of wave observations in the Arctic marginal ice zone with spectral models
Increased economic activity and research interest in the Arctic raise the need for better wave forecasts in the marginal ice zone (MIZ). Mathematical and numerical models of wave propagation in sea ice would benefit from more in situ data for validation. This study presents shipborne wave measurements from the MIZ wher...
2003.09472v3
2020-09-24
Kinetic energy dissipation and fluctuations in strongly-damped heavy-ion collisions within the stochastic mean-field approach
Background: Microscopic mean-field approaches have been successful in describing the most probable reaction outcomes in low-energy heavy-ion reactions. However, those approaches are known to severely underestimate dispersions of observables around the average values that has limited their applicability. Recently it has...
2009.11978v2
2021-01-21
A Gauss-Seidel projection method with the minimal number of updates for stray field in micromagnetic simulations
Magnetization dynamics in magnetic materials is often modeled by the Landau-Lifshitz equation, which is solved numerically in general. In micromagnetic simulations, the computational cost relies heavily on the time-marching scheme and the evaluation of stray field. Explicit marching schemes are efficient but suffer fro...
2101.08574v1
2022-07-06
Anisotropic Behavior of the Thermoelectric Power and the Thermal Conductivity in a Unidirectional Lateral Superlattice: A Typical Anisotropic System Exhibiting Two Distinct Nernst Coefficients
We have calculated the thermoelectric conductivity tensor $\varepsilon_{ij}$ and the thermal conductivity tensor $\lambda_{ij}$ of a unidirectional lateral superlattice (ULSL) ($i,j = x,y$, with the $x$-axis aligned to the principal axis of the ULSL), %, given as the first- and the second-order moments, employing based...
2207.02367v3
2022-07-13
Probing Bardeen-Kiselev black hole with cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds
In this work, we investigate a static and spherically symmetric Bardeen-Kiselev black hole with cosmological constant which is a solution of the Einstein-non-linear Maxwell field equations along with a quintessential field. We compute the quasinormal frequencies for Bardeen-Kiselev black hole(BH) with cosmological cons...
2207.05907v4
2022-07-29
Global spherically symmetric solutions to degenerate compressible Navier-Stokes equations with large data and far field vacuum
We consider the initial-boundary value problem (IBVP) for the isentropic compressible Navier-Stokes equations (\textbf{CNS}) in the domain exterior to a ball in $\mathbb R^d$ $(d=2\ \text{or} \ 3)$. When viscosity coefficients are given as a constant multiple of the mass density $\rho$, based on some analysis of the no...
2207.14494v1
2022-11-23
Lattice eddy simulation of turbulent flows
Kolmogorov's (1941) theory of self-similarity implies the universality of small-scale eddies, and holds promise for a universal sub-grid scale model for large eddy simulation. The fact is the empirical coefficient of a typical sub-grid scale model varies from 0.1 to 0.2 in free turbulence and damps gradually to zero ap...
2211.12810v1
1996-06-07
Abundances at High Redshifts: the Chemical Enrichment History of Damped Lyman-alpha Galaxies
Damped Lyman-alpha absorption systems found in the spectra of high redshift quasars are believed to trace the interstellar gas in high redshift galaxies. In this paper, we study the elemental abundances of C, N, O, Al, Si, S, Cr, Mn, Fe, Ni, and Zn in a sample of 14 damped Lyman-alpha systems using high quality echelle...
9606044v1
1998-07-17
Chaotic scattering on surfaces and collisional damping of collective modes
The damping of hot giant dipole resonances is investigated. The contribution of surface scattering is compared with the contribution from interparticle collisions. A unified response function is presented which includes surface damping as well as collisional damping. The surface damping enters the response via the Lyap...
9807185v4
2000-09-08
Probing High-Redshift Disks with Damped Lyman Alpha Systems
Evidence is presented that the damped Lyman alpha absorption systems are the high-redshift (z > 3) progenitors of galaxy disks. I discuss kinematic evidence that the damped Lyman Alpha systems are rotating disks. I also discuss implications of the lack of metal-poor damped Lyman alpha systems with line width Delta v > ...
0009126v1
2006-09-10
Damping of Compressional MHD Waves In Quiescent Prominences and Prominence-Corona Transition Region (PCTR)
The effects of radiative losses due to Newtonian cooling and MHD turbulence have been considered to examine the spatial damping of linear compressional waves in quiescent prominences and prominence-corona transition region (PCTR). The radiative losses give acceptable damping lengths for the slow mode wave for the radia...
0609266v1
1997-10-14
Damping of low-energy excitations of a trapped Bose condensate at finite temperatures
We present the theory of damping of low-energy excitations of a trapped Bose condensate at finite temperatures, where the damping is provided by the interaction of these excitations with the thermal excitations. We emphasize the key role of stochastization in the behavior of the thermal excitations for damping in non-s...
9710128v3
2001-12-09
Soliton dynamics in damped and forced Boussinesq equations
We investigate the dynamics of a lattice soliton on a monatomic chain in the presence of damping and external forces. We consider Stokes and hydrodynamical damping. In the quasi-continuum limit the discrete system leads to a damped and forced Boussinesq equation. By using a multiple-scale perturbation expansion up to s...
0112148v1
2006-04-17
The Highly Damped Quasinormal Modes of $d$-dimensional Reissner-Nordstrom Black Holes in the Small Charge Limit
We analyze in detail the highly damped quasinormal modes of $d$-dimensional Reissner-Nordstr$\ddot{\rm{o}}$m black holes with small charge, paying particular attention to the large but finite damping limit in which the Schwarzschild results should be valid. In the infinite damping limit, we confirm using different meth...
0604073v2
2005-02-16
Damping signatures in future neutrino oscillation experiments
We discuss the phenomenology of damping signatures in the neutrino oscillation probabilities, where either the oscillating terms or the probabilities can be damped. This approach is a possibility for tests of non-oscillation effects in future neutrino oscillation experiments, where we mainly focus on reactor and long-b...
0502147v2
1997-07-23
Riccati parameter modes from Newtonian free damping motion by supersymmetry
We determine the class of damped modes \tilde{y} which are related to the common free damping modes y by supersymmetry. They are obtained by employing the factorization of Newton's differential equation of motion for the free damped oscillator by means of the general solution of the corresponding Riccati equation toget...
9707019v4
2000-08-22
Local and Fundamental Mode Coupler Damping of the Transverse Wakefield in RDDS1 Linacs
In damping the wakefield generated by an electron beam traversing several thousand X-band linacs in the NLC we utilise a Gaussian frequency distribution of dipole modes to force the modes to deconstructively interfere, supplemented with moderate damping achieved by coupling these modes to four attached manifolds. Most ...
0008211v1
2007-10-25
Damping of Condensate Oscillation of a Trapped Bose Gas in a One-Dimensional Optical Lattice at Finite Temperatures
We study damping of a dipole oscillation in a Bose-Condensed gas in a combined cigar-shaped harmonic trap and one-dimensional (1D) optical lattice potential at finite temperatures. In order to include the effect of thermal excitations in the radial direction, we derive a quasi-1D model of the Gross-Pitaeavskii equation...
0710.4610v1
2008-01-03
Spin orbit precession damping in transition metal ferromagnets
We provide a simple explanation, based on an effective field, for the precession damping rate due to the spin-orbit interaction. Previous effective field treatments of spin-orbit damping include only variations of the state energies with respect to the magnetization direction, an effect referred to as the breathing Fer...
0801.0549v1
2009-02-03
Damping of filament thread oscillations: effect of the slow continuum
Transverse oscillations of small amplitude are commonly seen in high-resolution observations of filament threads, i.e. the fine-structures of solar filaments/prominences, and are typically damped in a few periods. Kink wave modes supported by the thread body offer a consistent explanation of these observed oscillations...
0902.0572v2
2010-11-23
Magnetohydrodynamic kink waves in two-dimensional non-uniform prominence threads
We analyse the oscillatory properties of resonantly damped transverse kink oscillations in two-dimensional prominence threads. The fine structures are modelled as cylindrically symmetric magnetic flux tubes with a dense central part with prominence plasma properties and an evacuated part, both surrounded by coronal pla...
1011.5175v2
2011-04-04
Plasmonic abilities of gold and silver spherical nanoantennas in terms of size dependent multipolar resonance frequencies and plasmon damping rates
Absorbing and emitting optical properties of a spherical plasmonic nanoantenna are described in terms of the size dependent resonance frequencies and damping rates of the multipolar surface plasmons (SP). We provide the plasmon size characteristics for gold and silver spherical particles up to the large size retardatio...
1104.0565v1
2011-11-16
Three-player quantum Kolkata restaurant problem under decoherence
Effect of quantum decoherence in a three-player quantum Kolkata restaurant problem is investigated using tripartite entangled qutrit states. Amplitude damping, depolarizing, phase damping, trit-phase flip and phase flip channels are considered to analyze the behaviour of players payoffs. It is seen that Alice's payoff ...
1111.3913v2
2012-07-27
The effect of non-uniform damping on flutter in axial flow and energy harvesting strategies
The problem of energy harvesting from flutter instabilities in flexible slender structures in axial flows is considered. In a recent study, we used a reduced order theoretical model of such a system to demonstrate the feasibility for harvesting energy from these structures. Following this preliminary study, we now cons...
1207.6484v1
2012-11-20
Damping rates of surface plasmons for particles of size from nano- to micrometers; reduction of the nonradiative decay
Damping rates of multipolar, localized surface plasmons (SP) of gold and silver nanospheres of radii up to $1000nm$ were found with the tools of classical electrodynamics. The significant increase in damping rates followed by noteworthy decrease for larger particles takes place along with substantial red-shift of plasm...
1211.4781v1
2013-10-23
Landau damping in a collisionless dipolar Bose gas
We present a theory for the Landau damping of low energy quasi-particles in a collisionless, quasi-2D dipolar Bose gas and produce expressions for the damping rate in uniform and non-uniform systems. Using simple energy-momentum conservation arguments, we show that in the homogeneous system, the nature of the low energ...
1310.6386v1
2014-01-15
Damping of Terahertz Plasmons in Graphene Coupled with Surface Plasmons in Heavily-Doped Substrate
Coupling of plasmons in graphene at terahert (THz) frequencies with surface plasmons in a heavily-doped substrate is studied theoretically. We reveal that a huge scattering rate may completely damp out the plasmons, so that proper choices of material and geometrical parameters are essential to suppress the coupling eff...
1401.3396v1
2014-11-28
Non-equilibrium thermodynamics of damped Timoshenko and damped Bresse systems
In this paper, we cast damped Timoshenko and damped Bresse systems into a general framework for non-equilibrium thermodynamics, namely the GENERIC (General Equation for Non-Equilibrium Reversible-Irreversible Coupling) framework. The main ingredients of GENERIC consist of five building blocks: a state space, a Poisson ...
1412.0038v2
2014-12-08
Bi-$\cal{PT}$ symmetry in nonlinearly damped dynamical systems and tailoring $\cal{PT}$ regions with position dependent loss-gain profiles
We investigate the remarkable role of position dependent damping in determining the parametric regions of symmetry breaking in nonlinear $\cal{PT}$-symmetric systems. We illustrate the nature of $\cal{PT}$-symmetry preservation and breaking with reference to a remarkable integrable scalar nonlinear system. In the two d...
1412.2574v3
2015-09-04
Damped transverse oscillations of interacting coronal loops
Damped transverse oscillations of magnetic loops are routinely observed in the solar corona. This phenomenon is interpreted as standing kink magnetohydrodynamic waves, which are damped by resonant absorption owing to plasma inhomogeneity across the magnetic field. The periods and damping times of these oscillations can...
1509.01487v1
2015-09-14
Beliaev damping in quasi-2D dipolar condensates
We study the effects of quasiparticle interactions in a quasi-two dimensional (quasi-2D), zero-temperature Bose-Einstein condensate of dipolar atoms, which can exhibit a roton-maxon feature in its quasiparticle spectrum. Our focus is the Beliaev damping process, in which a quasiparticle collides with the condensate and...
1509.04217v1
2015-12-08
Thermal energies of classical and quantum damped oscillators coupled to reservoirs
We consider the global thermal state of classical and quantum harmonic oscillators that interact with a reservoir. Ohmic damping of the oscillator can be exactly treated with a 1D scalar field reservoir, whereas general non-Ohmic damping is conveniently treated with a continuum reservoir of harmonic oscillators. Using ...
1512.02551v2
2016-10-10
A Five-Freedom Active Damping and Alignment Device Used in the Joule Balance
Damping devices are necessary for suppressing the undesired coil motions in the watt/joule balance. In this paper, an active electromagnetic damping device, located outside the main magnet, is introduced in the joule balance project. The presented damping device can be used in both dynamic and static measurement modes....
1610.02799v1
2017-10-10
A four-field gyrofluid model with neoclassical effects for the study of the rotation velocity of magnetic islands in tokamaks
A four-field system of equations which includes the neoclassical flow damping effects and the lowest-order finite-Larmor-radius (FLR) corrections is deduced from a system of gyrofluid equations. The FLR corrections to the poloidal flow damping are calculated by solving a simplified version of the gyrokinetic equation. ...
1710.03585v1
2017-12-04
Resonance oscillation of a damped driven simple pendulum
The resonance characteristics of a driven damped harmonic oscillator are well known. Unlike harmonic oscillators which are guided by parabolic potentials, a simple pendulum oscillates under sinusoidal potentials. The problem of an undamped pendulum has been investigated to a great extent. However, the resonance charact...
1712.01032v1
2018-01-17
On Global Existence and Blow-up for Damped Stochastic Nonlinear Schrödinger Equation
In this paper, we consider the well-posedness of the weakly damped stochastic nonlinear Schr\"odinger(NLS) equation driven by multiplicative noise. First, we show the global existence of the unique solution for the damped stochastic NLS equation in critical case. Meanwhile, the exponential integrability of the solution...
1801.05630v1
2018-03-29
Giant resonant nonlinear damping in nanoscale ferromagnets
Magnetic damping is a key metric for emerging technologies based on magnetic nanoparticles, such as spin torque memory and high-resolution biomagnetic imaging. Despite its importance, understanding of magnetic dissipation in nanoscale ferromagnets remains elusive, and the damping is often treated as a phenomenological ...
1803.10925v1
2019-03-01
Comprehensive Study of Neutrino-Dark Matter Mixed Damping
Mixed damping is a physical effect that occurs when a heavy species is coupled to a relativistic fluid which is itself free streaming. As a cross-case between collisional damping and free-streaming, it is crucial in the context of neutrino-dark matter interactions. In this work, we establish the parameter space relevan...
1903.00540v2
2019-08-04
Efficient spin excitation via ultrafast damping-like torques in antiferromagnets
Damping effects form the core of many emerging concepts for high-speed spintronic applications. Important characteristics such as device switching times and magnetic domain-wall velocities depend critically on the damping rate. While the implications of spin damping for relaxation processes are intensively studied, dam...
1908.01359v3
2019-10-31
Gyrokinetic investigation of the damping channels of Alfvén modes in ASDEX Upgrade
The linear destabilization and nonlinear saturation of energetic-particle driven Alfv\'enic instabilities in tokamaks strongly depend on the damping channels. In this work, the collisionless damping mechanisms of Alfv\'enic modes are investigated within a gyrokinetic framework, by means of global simulations with the p...
1910.14489v1
2020-12-27
Quantum speed limit time in relativistic frame
We investigate the roles of the relativistic effect on the speed of evolution of a quantum system coupled with amplitude damping channels. We find that the relativistic effect speed-up the quantum evolution to a uniform evolution speed of open quantum systems for the damping parameter $p_{\tau}\lesssim p_{\tau_{c0}}.$ ...
2012.13859v2
2021-06-23
Regularization of central forces with damping in two and three-dimensions
Regularization of damped motion under central forces in two and three-dimensions are investigated and equivalent, undamped systems are obtained. The dynamics of a particle moving in $\frac{1}{r}$ potential and subjected to a damping force is shown to be regularized a la Levi-Civita. We then generalize this regularizati...
2106.12134v1
2021-07-06
Theory of vibrators with variable-order fractional forces
In this paper, we present a theory of six classes of vibrators with variable-order fractional forces of inertia, damping, and restoration. The novelty and contributions of the present theory are reflected in six aspects. 1) Equivalent motion equations of those variable-order fractional vibrators are proposed. 2) The an...
2107.02340v2
2021-08-15
Exponential stability of a damped beam-string-beam transmission problem
We consider a beam-string-beam transmission problem, where two structurally damped or undamped beams are coupled with a frictionally damped string by transmission conditions. We show that for this type of structure, the dissipation produced by the frictional part is strong enough to produce exponential decay of the sol...
2108.06749v1
2021-09-10
Fourth-order dynamics of the damped harmonic oscillator
It is shown that the classical damped harmonic oscillator belongs to the family of fourth-order Pais-Uhlenbeck oscillators. It follows that the solutions to the damped harmonic oscillator equation make the Pais-Uhlenbeck action stationary. Two systematic approaches are given for deriving the Pais-Uhlenbeck action from ...
2109.06034v1
2022-01-13
Damping of Alfvén waves in MHD turbulence and implications for cosmic ray streaming instability and galactic winds
Alfv\'{e}nic component of MHD turbulence damps Alfv\'{e}nic waves. The consequences of this effect are important for many processes, from cosmic ray (CR) propagation to launching outflows and winds in galaxies and other magnetized systems. We discuss the differences in the damping of the streaming instability by turbul...
2201.05168v1
2022-03-14
Investigation of nonlinear squeeze-film damping involving rarefied gas effect in micro-electro-mechanical-systems
In this paper, the nonlinear squeeze-film damping (SFD) involving rarefied gas effect in the micro-electro-mechanical-systems (MEMS) is investigated. Considering the motion of structures (beam, cantilever, and membrane) in MEMS, the dynamic response of structure will be influenced largely by the squeeze-film damping. I...
2203.06902v1
2022-05-21
Noether symmetries and first integrals of damped harmonic oscillator
Noether theorem establishes an interesting connection between symmetries of the action integral and conservation laws of a dynamical system. The aim of the present work is to classify the damped harmonic oscillator problem with respect to Noether symmetries and to construct corresponding conservation laws for all over-...
2205.10525v1
2023-01-31
The emergence of soft-glassy mechanics in simulated foams
Several seemingly different soft materials, including foams, cells, and many complex fluids, exhibit remarkably similar rheological properties and microscopic dynamics, termed soft glassy mechanics. Here, we show that such behavior emerges from a simple model of a damped ripening foam, for sufficiently weak damping. In...
2301.13400v1
2023-02-13
Thickness and temperature dependent damping in La$_{0.67}$Sr$_{0.33}$MnO$_{3}$ epitaxial films
The damping of La0.67Sr0.33MnO3 (LSMO) epitaxial films as a function of thickness at different temperatures was studied. The competition between two scattering types (\r{ho}-like and {\sigma}-like) with entirely distinct thickness and temperature dependencies resulted in complicated damping behavior. The behavior of {\...
2302.06099v3
1998-05-07
Discovery of z=0.0912 and z=0.2212 Damped Lyman-alpha Absorption Line Systems Toward the Quasar OI 363: Limits on the Nature of Damped Lyman-alpha Galaxies
The discovery of a z_abs = 0.0912 damped Lyman-alpha absorption-line system in the HST-FOS ultraviolet spectrum of the quasar OI 363 (0738+313) is reported. This is the lowest redshift quasar damped Lyman-alpha system known. Its neutral hydrogen column density is N(HI) = 1.5(+/- 0.2) E21 atoms/cm^2, which easily exceed...
9805093v1
2008-01-24
Attenuation of small-amplitude oscillations in a prominence-corona model with a transverse magnetic field
Small-amplitude prominence oscillations are usually damped after a few periods. We study the attenuation of non-adiabatic magnetoacoustic waves in a slab prominence embedded in the coronal medium. We assume an equilibrium configuration with a transverse magnetic field to the slab axis and investigate wave damping by th...
0801.3744v2
2010-04-26
Selective spatial damping of propagating kink waves due to resonant absorption
There is observational evidence of propagating kink waves driven by photospheric motions. These disturbances, interpreted as kink magnetohydrodynamic (MHD) waves are attenuated as they propagate upwards in the solar corona. In this paper we show that resonant absorption provides a simple explanation to the spatial damp...
1004.4468v1
2011-04-10
Spatial Damping of Propagating Kink Waves Due to Resonant Absorption: Effect of Background Flow
Observations show the ubiquitous presence of propagating magnetohydrodynamic (MHD) kink waves in the solar atmosphere. Waves and flows are often observed simultaneously. Due to plasma inhomogeneity in the perpendicular direction to the magnetic field, kink waves are spatially damped by resonant absorption. The presence...
1104.1791v1
2013-02-08
On the Damping-Induced Self-Recovery Phenomenon in Mechanical Systems with Several Unactuated Cyclic Variables
The damping-induced self-recovery phenomenon refers to the fundamental property of underactuated mechanical systems: if an unactuated cyclic variable is under a viscous damping-like force and the system starts from rest, then the cyclic variable will always move back to its initial condition as the actuated variables c...
1302.2109v1
2016-07-06
Damping of Alfven waves by Turbulence and its Consequences: from Cosmic-Rays Streaming to Launching Winds
This paper considers turbulent damping of Alfven waves in magnetized plasmas. We identify two cases of damping, one related to damping of cosmic rays streaming instability, the other related to damping of Alfven waves emitted by a macroscopic wave source, e.g. stellar atmosphere. The physical difference between the two...
1607.02042v1
2018-01-18
Quantum Landau damping in dipolar Bose-Einstein condensates
We consider Landau damping of elementary excitations in Bose-Einstein condensates (BECs) with dipolar interactions. We discuss quantum and quasi-classical regimes of Landau damping. We use a generalized wave-kinetic description of BECs which, apart from the long range dipolar interactions, also takes into account the q...
1801.06256v1
2020-05-31
Optimal decay rates of the compressible Euler equations with time-dependent damping in $\mathbb R^n$: (I) under-damping case
This paper is concerned with the multi-dimensional compressible Euler equations with time-dependent damping of the form $-\frac{\mu}{(1+t)^\lambda}\rho\boldsymbol u$ in $\mathbb R^n$, where $n\ge2$, $\mu>0$, and $\lambda\in[0,1)$. When $\lambda>0$ is bigger, the damping effect time-asymptotically gets weaker, which is ...
2006.00401v1
2022-08-17
Anti-parity-time symmetry hidden in a damping linear resonator
Phase transition from the over-damping to under-damping states is a ubiquitous phenomenon in physical systems. However, what kind of symmetry is broken associated with this phase transition remains unclear. Here, we discover that this phase transition is determined by an anti-parity-time (anti-$\mathcal{PT}$) symmetry ...
2208.08187v2
1996-12-10
Collisional matter-phase damping in Bose-condensed gas
Collisional damping of the excitations in a Bose-condensed gas is investigated over the wide range of energies and temperatures. Numerical results for the damping rate are presented and a number of asymptotic and interpolating expressions for it are derived.
9612086v1
2001-11-29
Tensor form of magnetization damping
A tensor form of phenomenological damping is derived for small magnetization motions. This form reflects basic physical relaxation processes for a general uniformly magnetized particle or film. Scalar Landau-Lifshitz damping is found to occur only for two special cases of system symmetry.
0111566v1
1999-07-28
An effective relaxation-time approach to collisionless quark-gluon plasma
We present an effective relaxation-time theory to study the collisionless quark-gluon plasma. Applying this method we calculate the damping rate to be of order $g^2T$ and find plasmon scattering is the damping mechanism. The damping for the transverse mode is stronger than the longitudinal one.
9907526v1
1999-11-16
Dynamical resummation and damping in the O(N) model
A general real-time formalism is developed to resum the self-energy operator of broken symmetry scalar field theories in form of self-consistent gap equations for the spectral function. The solution of the equations is approximated with finite lifetime quasi-particles. In the Landau damping rates viscosity terms, analo...
9911374v1
1993-03-24
On the Quantizations of the Damped Systems
Based on a simple observation that a classical second order differential equation may be decomposed into a set of two first order equations, we introduce a Hamiltonian framework to quantize the damped systems. In particular, we analyze the system of a linear damped harmonic oscillator and demonstrate that the time evol...
9303137v1
2006-01-09
Energy decay for damped wave equations on partially rectangular domains
We consider the wave equation with a damping term on a partially rectangular planar domain, assuming that the damping is concentrated close to the non-rectangular part of the domain. Polynomial decay estimates for the energy of the solution are established.
0601195v1
2002-06-07
Resonant states and classical damping
Using Koopman's approach to classical dynamical systems we show that the classical damping may be interpreted as appearance of resonant states of the corresponding Koopman's operator. It turns out that simple classical damped systems give rise to discrete complex spectra. Therefore, the corresponding generalized eigenv...
0206009v1
2002-12-19
Trapped particle bounds on stimulated scatter in the large k/kD regime
In the strongly damped regime, the convective gain rate for stimulated scatter varies inversely with the plasma wave damping rate. Electron trapping effects reduce the damping but also lead to loss of resonance for large enough amplitude waves. This leads to a gain rate bound and corresponding optimum scattered light f...
0212071v1
2003-02-03
Oscillator damping with more than one mechanism of internal friction dissipation
The author's modified Coulomb damping model has been generalized to accommodate internal friction that derives from several dissipation mechanisms acting simultaneously. Because of its fundamental nonlinear nature, internal friction damping causes the quality factor Q of an oscillator in free-decay to change in time. E...
0302003v1
2003-02-15
Anisotropic Internal Friction Damping
The mechanical damping properties of sheet polaroid material have been studied with a physical pendulum. The polaroid samples were placed under the knife-edges of the pendulum, which was operated in free-decay at a period in the vicinity of 10 s. With the edges oriented parallel to the direction of the long molecular c...
0302055v1
2006-08-07
Study of the Damped Pendulum
Experiments on the oscillatory motion of a suspended bar magnet throws light on the damping effects acting on the pendulum. The viscous drag offered by air was found the be the main contributor for slowing the pendulum down. The nature and magnitude of the damping effects were shown to be strongly dependent on the ampl...
0608071v1
1995-02-27
Quantum Oscillator with Kronig-Penney Excitation in Different Regimes of Damping
There are discussed the exact solution of the time--dependent Schr\"{o}dinger equation for a damped quantum oscillator subject to a periodical frequency delta--kicks describing squeezed states which are expressed in terms of Chebyshev polynomials. The cases of strong and weak damping are investigated in the frame of Ca...
9502023v1
2007-03-12
Quantum estimation of a damping constant
We discuss an interferometric approach to the estimation of quantum mechanical damping. We study specific classes of entangled and separable probe states consisting of superpositions of coherent states. Based on the assumption of limited quantum resources we show that entanglement improves the estimation of an unknown ...
0703091v2
2008-11-07
Asymptotic stability of the wave equation on compact surfaces and locally distributed damping - A sharp result
This paper is concerned with the study of the wave equation on compact surfaces and locally distributed damping. We study the case where the damping is effective in a well-chosen subset of arbitrarily small measure.
0811.1190v1
2008-11-07
Uniform Stabilization of the wave equation on compact surfaces and locally distributed damping
This paper is concerned with the study of the wave equation on compact surfaces and locally distributed damping. We study the case where the damping is effective on the complement of visible umbilical sets.
0811.1204v1
2010-11-20
Enhanced damping of ion acoustic waves in dense plasmas
A theory for the ion acoustic wave damping in dense plasmas and warm dense matter, accounting for the Umklapp process, is presented. A higher decay rate compared to the prediction from the Landau damping theory is predicted for high-Z dense plasmas where the electron density ranges from $10^{21}$ to $ 10^{24} \mathrm{c...
1011.4607v1
2012-05-16
Enhanced coupling design of a detuned damped structure for clic
The key feature of the improved coupling design in the Damped Detuned Structure (DDS) is focused on the four manifolds. Rectangular geometry slots and rectangular manifolds are used. This results in a significantly stronger coupling to the manifolds compared to the previous design. We describe the new design together w...
1205.3590v1
2012-06-26
On the $L^{2}$-critical nonlinear Schrödinger Equation with a nonlinear damping
We consider the Cauchy problem for the $L^{2}$-critical nonlinear Schr\"{o}dinger equation with a nonlinear damping. According to the power of the damping term, we prove the global existence or the existence of finite time blowup dynamics with the log-log blow-up speed for $\|\nabla u(t)\|_{L^2}$.
1206.6082v4
2012-10-12
Semi-linear wave equations with effective damping
We study the Cauchy problem for the semi-linear damped wave equation in any space dimension. We assume that the time-dependent damping term is effective. We prove the global existence of small energy data solutions in the supercritical case.
1210.3493v1
2012-12-10
Strongly damped wave equation with exponential nonlinearities
In this paper, we study the initial boundary value problem for the two dimensional strong damped wave equation with exponentially growing source and damping terms. We first show the well-posedness of this problem and then prove the existence of the global attractor in $(H_{0}^{1}(\Omega)\cap L^{\infty}(\Omega))\times L...
1212.2180v2
2013-10-27
Exponential decay of solutions for the plate equation with localized damping
In this paper, we give positive answer to the open question raised in [E. Zuazua, Exponential decay for the semilinear wave equation with localized damping in unbounded domains. J. Math. Pures Appl., 70 (1991) 513--529] on the exponential decay of solutions for the semilinear plate equation with localized damping.
1310.7243v3
2014-03-07
Landau damping in Sobolev spaces for the Vlasov-HMF model
We consider the Vlasov-HMF (Hamiltonian Mean-Field) model. We consider solutions starting in a small Sobolev neighborhood of a spatially homogeneous state satisfying a linearized stability criterion (Penrose criterion). We prove that these solutions exhibit a scattering behavior to a modified state, which implies a non...
1403.1668v2
2015-03-30
Damping to prevent the blow-up of the Korteweg-de Vries equation
We study the behavior of the solution of a generalized damped KdV equation $u_t + u_x + u_{xxx} + u^p u_x + \mathscr{L}_{\gamma}(u)= 0$. We first state results on the local well-posedness. Then when $p \geq 4$, conditions on $\mathscr{L}_{\gamma}$ are given to prevent the blow-up of the solution. Finally, we numericall...
1503.08559v1
2015-11-25
A Proposal of a Damping Term for the Relativistic Euler Equations
We introduce a damping term for the special relativistic Euler equations in $3$-D and show that the equations reduce to the non-relativistic damped Euler equations in the Newtonian limit. We then write the equations as a symmetric hyperbolic system for which local-in-time existence of smooth solutions can be shown.
1511.08183v1
2016-01-27
Concatenated Codes for Amplitude Damping
We discuss a method to construct quantum codes correcting amplitude damping errors via code concatenation. The inner codes are chosen as asymmetric Calderbank-Shor-Steane (CSS) codes. By concatenating with outer codes correcting symmetric errors, many new codes with good parameters are found, which are better than the ...
1601.07423v1
2016-03-29
Generalized damped Milne-Pinney equation and Chiellini method
We adopt the Chiellini integrability method to find the solutions of various generalizations of the damped Milne-Pinney equations. In particular, we find the solution of the damped Ermakov-Painlev\'e II equation and generalized dissipative Milne-Pinney equation.
1603.08747v2
2017-12-07
Damped wave equations on compact hyperbolic surfaces
We prove exponential decay of energy for solutions of the damped wave equation on compact hyperbolic surfaces with regular initial data as long as the damping is nontrivial. The proof is based on a similar strategy as in Dyatlov-Jin and in particular, uses the fractal uncertainty principle proved in Bourgain-Dyatlov.
1712.02692v1
2018-09-10
Logarithmic Decay of a Wave Equation with Kelvin-Voigt Damping
In this paper we analyze the long time behavior of a wave equation with local Kelvin-Voigt Damping. Through introducing proper class symbol and pseudo-differential calculus, we obtain a Carleman estimate, and then establish an estimate on the corresponding resolvent operator. As a result, we show the logarithmic decay ...
1809.03196v1
2018-11-07
Slow-dissipation limit of the harmonic oscillator with general power-law damping
An approximate solution is presented for simple harmonic motion in the presence of damping by a force which is a general power-law function of the velocity. The approximation is shown to be quite robust, allowing for a simple way to investigate amplitude decay in the presence of general types of weak, nonlinear damping...
1811.02953v2
2019-09-25
Forced Coupled Duffing Oscillators with Nonlinear Damping: Resonance and Antiresonance
In this work, we investigate resonance and antiresonance behaviour in forced coupled Duffing oscillators with nonlinear damping. Further, we will analyse the parameter dependence of the frequency response and stability. In the course of all the analysis, emphasis shall be on how different damping mechanisms contrast ag...
1909.11390v1
2020-04-21
Damping rate limitations for transverse dampers in large hadron colliders
The paper focuses on two issues important for design and operation of bunch-by-bunch transverse damper in a very large hadron collider, where fast damping is required to suppress beam instabilities and noise induced emittance growth. The first issue is associated with kick variation along a bunch which affects the damp...
2004.10249v2
2021-02-01
Global existence for semilinear wave equations with scaling invariant damping in 3-D
Global existence for small data Cauchy problem of semilinear wave equations with scaling invariant damping in 3-D is established in this work, assuming that the data are radial and the constant in front of the damping belongs to $[1.5, 2)$. The proof is based on a weighted $L^2-L^2$ estimate for inhomogeneous wave equa...
2102.00909v1
2022-02-10
Stochastic optimal control for nonlinear damped network dynamics
We present a stochastic optimal control problem for a tree network. The dynamics of the network are governed by transport equations with a special emphasis on the non-linear damping function. Demand profiles at the network sinks are modelled by a stochastic differential equations. An explicit optimal inflow into the ne...
2202.05114v1
2022-03-03
Conformal symmetry in damped Pais-Uhlenbeck oscillator
Two Lagrangian formulations for describing of the damped harmonic oscillator have been introduced by Bateman. For these models we construct higher derivative generalization which enjoys the l-conformal Newton-Hooke symmetry. The dynamics of generalized systems corresponds to the damped Pais-Uhlenbeck oscillator for a p...
2203.01651v1
2022-10-31
An adaptive damped Newton method for strongly monotone and Lipschitz continuous operator equations
We will consider the damped Newton method for strongly monotone and Lipschitz continuous operator equations in a variational setting. We will provide a very accessible justification why the undamped Newton method performs better than its damped counterparts in a vicinity of a solution. Moreover, in the given setting, a...
2210.17107v1
2022-11-19
Blow up and lifespan estimates for systems of semi-linear wave equations with damping and potential
In this paper, we consider the semi-linear wave systems with power-nonlinearities and a large class of space-dependent damping and potential. We obtain the same blow-up regions and the lifespan estimates for three types wave systems, compared with the systems without damping and potential.
2211.10639v1
2023-08-10
Pathwise uniqueness for stochastic heat and damped equations with Hölder continuous drift
In this paper, we prove pathwise uniqueness for stochastic differential equations in infinite dimension. Under our assumptions, we are able to consider the stochastic heat equation up to dimension $3$, the stochastic damped wave equation in dimension $1$ and the stochastic Euler-Bernoulli damped beam equation up to dim...
2308.05415v1