publicationDate stringlengths 1 2.79k | title stringlengths 1 36.5k ⌀ | abstract stringlengths 1 37.3k ⌀ | id stringlengths 9 47 |
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2002-01-16 | Quantum Spin dynamics of the Bilayer Ferromagnet La(1.2)Sr(1.8)Mn2O7 | We construct a theory of spin wave excitations in the bilayer manganite
La(1.2)Sr(1.8)Mn2O7 based on the simplest possible double-exchange model, but
including leading quantum corrections to the spin wave dispersion and damping.
Comparison is made with recent inelastic neutron scattering experiments. We
find that quant... | 0201269v1 |
2002-02-21 | Dynamics of a Bose-Einstein condensate at finite temperature in an atomoptical coherence filter | The macroscopic coherent tunneling through the barriers of a periodic
potential is used as an atomoptical filter to separate the condensate and the
thermal components of a $^{87}$Rb mixed cloud. We condense in the combined
potential of a laser standing-wave superimposed on the axis of a cigar-shape
magnetic trap and in... | 0202369v1 |
2002-03-11 | A Damping of the de Haas-van Alphen Oscillations in the superconducting state | Deploying a recently developed semiclassical theory of quasiparticles in the
superconducting state we study the de Haas-van Alphen effect. We find that the
oscillations have the same frequency as in the normal state but their amplitude
is reduced. We find an analytic formulae for this damping which is due to
tunnelling... | 0203224v1 |
2002-03-26 | Measurement induced quantum-classical transition | A model of an electrical point contact coupled to a mechanical system
(oscillator) is studied to simulate the dephasing effect of measurement on a
quantum system. The problem is solved at zero temperature under conditions of
strong non-equilibrium in the measurement apparatus. For linear coupling
between the oscillator... | 0203521v3 |
2002-07-04 | Fluctuations and correlations in hexagonal optical patterns | We analyze the influence of noise in transverse hexagonal patterns in
nonlinear Kerr cavities. The near field fluctuations are determined by the
neutrally stable Goldstone modes associated to translational invariance and by
the weakly damped soft modes. However these modes do not contribute to the far
field intensity f... | 0207127v2 |
2002-09-19 | Damping of long-wavelength collective excitations in quasi-onedimensional Fermi liquids | The imaginary part of the exchange-correlation kernel in the longitudinal
current-current response function of a quasi-onedimensional Fermi liquid is
evaluated by an approximate decoupling in the equation of motion for the
current density, which accounts for processes of excitation of two
particle-hole pairs. The two-p... | 0209455v1 |
2002-11-01 | Exploring dynamical magnetism with time-dependent density-functional theory: from spin fluctuations to Gilbert damping | We use time-dependent spin-density-functional theory to study dynamical
magnetic phenomena. First, we recall that the local-spin-density approximation
(LSDA) fails to account correctly for magnetic fluctuations in the paramagnetic
state of iron and other itinerant ferromagnets. Next, we construct a
gradient-dependent d... | 0211021v1 |
2002-11-05 | Magnetic fluctuations and resonant peak in cuprates: a microscopic theory | The theory for the dynamical spin susceptibility within the t-J model is
developed, as relevant for the resonant magnetic peak and normal-state magnetic
response in superconducting (SC) cuprates. The analysis is based on the
equations of motion for spins and the memory-function presentation of magnetic
response where t... | 0211090v1 |
2002-11-20 | Damping of Nodal Fermions Caused by a Dissipative Mode | Using a $d_{x^2 - y^2}$ superconductor in 2+1 dimensions we show that the
Nambu Goldstone fluctuations are replaced by dissipative excitations. We find
that the nodal quasi-particles damping is caused by the strong dissipative
excitations near the nodal points. As a result we find that the scattering
rates are linear i... | 0211440v1 |
2002-11-22 | Nonlinear microscopic relaxation of uniform magnetization precession | Dynamic relaxation for nonlinear magnetization excitation is analyzed. For
direct processes, such as magnon-electron scattering and two-magnon scattering,
the relaxation rate is determined from the linear case simply by utilizing the
magnetization oscillation frequency for nonlinear excitation. For an indirect
process,... | 0211499v1 |
2003-04-04 | Dynamic exchange coupling and Gilbert damping in magnetic multilayers | We theoretically study dynamic properties of thin ferromagnetic films in
contact with normal metals. Moving magnetizations cause a flow of spins into
adjacent conductors, which relax by spin flip, scatter back into the
ferromagnet, or are absorbed by another ferromagnet. Relaxation of spins
outside the moving magnetiza... | 0304116v1 |
2003-05-27 | Dynamics of a classical gas including dissipative and mean field effects | By means of a scaling ansatz, we investigate an approximated solution of the
Boltzmann-Vlasov equation for a classical gas. Within this framework, we derive
the frequencies and the damping of the collective oscillations of a
harmonically trapped gas and we investigate its expansion after release of the
trap. The method... | 0305624v1 |
2003-07-21 | Chaotic scattering of a quantum particle weakly coupled to a very complicated background | Effect of a complicated many-body environment is analyzed on the chaotic
motion of a quantum particle in a mesoscopic ballistic structure. The dephasing
and absorption phenomena are treated on the same footing in the framework of a
model which is free of the ambiguities inherent to earlier models. The
single-particle d... | 0307496v1 |
2003-11-21 | Self-stabilised fractality of sea-coasts through damped erosion | Erosion of rocky coasts spontaneously creates irregular seashores. But the
geometrical irregularity, in turn, damps the sea-waves, decreasing the average
wave amplitude. There may then exist a mutual self-stabilisation of the waves
amplitude together with the irregular morphology of the coast. A simple model
of such st... | 0311509v1 |
2003-12-10 | Exciton-LO-phonon dynamics in InAs/GaAs quantum dots: Effects of zone-edge phonon damping | The dynamics of an exciton-LO-phonon system after an ultrafast optical
excitation in an InAs/GaAs quantum dot is studied theoretically. Influence of
anharmonic phonon damping and its interplay with the phonon dispersion is
analyzed. The signatures of the zone-edge decay process in the absorption
spectrum and time evolu... | 0312256v2 |
2004-01-13 | Vortex waves and the onset of turbulence in $^3$He-B | In a recent experiment Finne et al. discovered an intrinsic condition for the
onset of quantum turbulence in $^3$He-B, that q=alpha/(1-alpha')<1, where alpha
and alpha' are mutual friction parameters. The authors argued that this
condition corresponds to Kelvin waves which are marginally damped, so for q>1
Kelvin waves... | 0401212v1 |
2004-01-28 | Long lived acoustic vibrational modes of an embedded nanoparticle | Classical continuum elastic calculations show that the acoustic vibrational
modes of an embedded nanoparticle can be lightly damped even when the
longitudinal plane wave acoustic impedances $Z_o=\rho v_L$ of the nanoparticle
and the matrix are the same. It is not necessary for the matrix to be less
dense or softer than... | 0401579v2 |
2004-07-20 | Dynamics of a trapped ultracold two-dimensional atomic gas | This article is devoted to the study of two-dimensional Bose gases
harmonically confined. We first summarize their equilibrium properties. For
such a gas above the critical temperature, we also derive the frequencies and
the damping of the collective oscillations and we investigate its expansion
after releasing of the ... | 0407522v1 |
2004-12-06 | Thermal wave packets induced by attosecond laser pulses | In this paper the dynamics of the interaction of attosecond laser pulses with
matter is investigated. It will be shown that the master equation: modified
Klein-Gordon equation describes the propagation of the heatons. Heatons are the
thermal wave packets. When the duration of the laser pulsees \delta t is of the
order ... | 0412126v1 |
2005-04-12 | Nonlinear response and discrete breather excitation in driven micro-mechanical cantilever arrays | We explain the origin of the generation of discrete breathers (DBs) in
experiments on damped and driven micromechanical cantilever arrays (M.Sato et
al. Phys. Rev. Lett. {\bf 90}, 044102, 2003). Using the concept of the
nonlinear response manifold (NLRM) we provide a systematic way to find the
optimal parameter regime ... | 0504298v1 |
2005-05-14 | Monopole Oscillations and Dampings in Boson and Fermion Mixture in the Time-Dependent Gross-Pitaevskii and Vlasov Equations | We construct a dynamical model for the time evolution of the boson-fermion
coexistence system. The dynamics of bosons and fermions are formulated with the
time-dependent Gross-Pitaevsky equation and the Vlasov equation. We thus study
the monopole oscillation in the bose-fermi mixture. We find that large damping
exists ... | 0505357v1 |
2005-10-11 | Non-damping magnetization oscillations in a single-domain ferromagnet | Non-damped oscillations of the magnetization vector of a ferromagnetic system
subject to a spin polarized current and an external magnetic field are studied
theoretically by solving the Landau-Lifshitz-Gilbert equation. It is shown that
the frequency and amplitude of such oscillations can be controlled by means of
an a... | 0510280v1 |
2005-10-13 | Superconducting Flywheel Model for Energy Storage Applications | In order to explore the complexity and diversity of the flywheels' dynamics,
we have developed the real-physics computer model of a universal mechanical
rotor. Due to an arbitrary external force concept, the model can be adjusted to
operate identical to the real experimental prototype. Taking the high-speed
magnetic ro... | 0510346v1 |
2005-12-03 | Apparent vibrational side-bands in pi-conjugated systems: the case of distyrylbenzene | The photoluminescence (PL) spectra of dilute solution and single crystals of
distyrylbenzene show unique temperature dependent vibronic structures. The
characteristic single frequency progression at high temperatures is modulated
by a low frequency progression series at low temperatures. None of the series
side band mo... | 0512067v1 |
2006-05-26 | Thermo-Plasma Polariton within Scaling Theory of Single-Layer Graphene | Electrodynamics of single-layer graphene is studied in the scaling regime. At
any finite temperature, there is a weakly damped collective thermo-plasma
polariton mode whose dispersion and wavelength dependent damping is determined
analytically. The electric and magnetic fields associated with this mode decay
exponentia... | 0605642v1 |
2006-12-18 | Shear viscosity and damping for a Fermi gas in the unitarity limit | The shear viscosity of a two-component Fermi gas in the normal phase is
calculated as a function of temperature in the unitarity limit, taking into
account strong-coupling effects that give rise to a pseudogap in the spectral
density for single-particle excitations. The results indicate that recent
measurements of the ... | 0612460v2 |
2007-02-07 | Damping of antiferromagnetic spin waves by valence fluctuations in the double layer perovskite YBaFe2O5 | Inelastic neutron scattering experiments show that spin dynamics in the
charge ordered insulating ground state of the double-layer perovskite YBaFe2O5
is well described in terms of eg superexchange interactions. Above the Verwey
transition at TV = 308 K, t2g double exchange-type conduction within
antiferromagnetic FeO2... | 0702181v1 |
2007-02-20 | Spin Drag and Spin-Charge Separation in Cold Fermi Gases | Low-energy spin and charge excitations of one-dimensional interacting
fermions are completely decoupled and propagate with different velocities.
These modes however can decay due to several possible mechanisms. In this paper
we expose a new facet of spin-charge separation: not only the speeds but also
the damping rates... | 0702466v1 |
2007-03-27 | Gauge Field Formulation of Adiabatic Spin Torques | Previous calculation of spin torques for small-amplitude magnetization
dynamics around a uniformly magnetized state [J. Phys. Soc. Jpn. {\bf 75}
(2006) 113706] is extended here to the case of finite-amplitude dynamics. This
is achieved by introducing an `` adiabatic'' spin frame for conduction
electrons, and the associ... | 0703705v1 |
1996-07-23 | Quasinormal modes of nearly extreme Reissner-Nordstrom black holes | We present detailed calculations of the quasinormal modes of
Reissner-Nordstrom black holes. While the first few, slowly damped, modes
depend on the charge of the black hole in a relatively simple way, we find that
the rapidly damped modes show several peculiar features. The higher modes
generally spiral into the value... | 9607054v1 |
1996-08-22 | Gravitational Ionization: A Chaotic Net in the Kepler System | The long term nonlinear dynamics of a Keplerian binary system under the
combined influences of gravitational radiation damping and external tidal
perturbations is analyzed. Gravitational radiation reaction leads the binary
system towards eventual collapse, while the external periodic perturbations
could lead to the ion... | 9608054v1 |
1999-11-11 | Inertial Control of the VIRGO Superattenuator | The VIRGO superattenuator (SA) is effective in depressing the seismic noise
below the thermal noise level above 4 Hz. On the other hand, the residual
mirror motion associated to the SA normal modes can saturate the dynamics of
the interferometer locking system. This motion is reduced implementing a
wideband (DC-5 Hz) m... | 9911044v1 |
2002-04-29 | Schwarzschild black holes and propagation of electromagnetic and gravitational waves | Disturbing of a spacetime geometry may result in the appearance of an
oscillating and damped radiation - the so-called quasinormal modes. Their
periods of oscillations and damping coefficients carry unique information about
the mass and the angular momentum, that would allow one to identify the source
of the gravitatio... | 0204086v1 |
2002-10-30 | Massive charged scalar field in a Reissner-Nordstrom black hole background: quasinormal ringing | We compute characteristic (quasinormal) frequencies corresponding to decay of
a massive charged scalar field in a Reissner-Nordstrom black hole background.
It proves that, contrary to the behavior at very late times, at the stage of
quasinormal ringing the neutral perturbations will damp slower than the charged
ones. I... | 0210105v3 |
2003-03-20 | Dirac Quasi-Normal Modes in Schwarzschild Black Hole Spacetimes | We evaluate both the massless and the massive Dirac quasi-normal mode
frequencies in the Schwarzschild black hole spacetime using the WKB
approximation. For the massless case, we find that, similar to those for the
integral spin fields, the real parts of the frequencies increase with the
angular momentum number $\kappa... | 0303078v1 |
2003-07-31 | Effects of electrical charging on the mechanical Q of a fused silica disk | We report on the effects of an electrical charge on mechanical loss of a
fused silica disk. A degradation of Q was seen that correlated with charge on
the surface of the sample. We examine a number of models for charge damping,
including eddy current damping and loss due to polarization. We conclude that
rubbing fricti... | 0308001v1 |
2004-10-06 | Thermoelastic-damping noise from sapphire mirrors in a fundamental-noise-limited interferometer | We report the first high-precision interferometer using large sapphire
mirrors, and we present the first direct, broadband measurements of the
fundamental thermal noise in these mirrors. Our results agree well with the
thermoelastic-damping noise predictions of Braginsky, et al. [Phys. Lett. A
264, 1(1999)] and Cerdoni... | 0410028v1 |
2004-10-28 | Gravitational waves from neutron stars described by modern EOS | The frequencies and damping times of neutron star (and quark star)
oscillations have been computed using the most recent equations of state
available in the literature. We find that some of the empirical relations that
connect the frequencies and damping times of the modes to the mass and radius
of the star, and that w... | 0410140v1 |
2005-06-08 | Resonant growth of stellar oscillations by incident gravitational waves | Stellar oscillation under the combined influences of incident gravitational
wave and radiation loss is studied in a simple toy model. The star is
approximated as a uniform density ellipsoid in the Newtonian gravity including
radiation damping through quadrupole formula. The time evolution of the
oscillation is signific... | 0506047v1 |
2006-11-28 | Massive scalar field quasinormal modes of a Schwarzschild black hole surrounded by quintessence | We present the quasinormal frequencies of the massive scalar field in the
background of a Schwarzchild black hole surrounded by quintessence with the
third-order WKB method. The mass of the scalar field $u$ plays an important
role in studying the quasinormal frequencies, the real part of the frequencies
increases linea... | 0611146v2 |
1992-09-24 | Non-Abelian Boltzmann Equation for Mixing and Decoherence | We consider particle oscillations and their damping in second-quantized form.
We find that the damping or "decoherence" may be described by a Boltzmann-like
collision integral with "non-abelian blocking factors" (fermions). Earlier
results are generalized in that the momentum degrees of freedom are included
and that th... | 9209276v1 |
1993-06-03 | The heavy fermion damping rate puzzle | : We examine again the problem of the damping rate of a moving heavy fermion
in a hot plasma within the resummed perturbative theory of Pisarski and
Braaten. The ansatz for its evaluation which relates it to the imaginary part
of the fermion propagator pole in the framework of a self-consistent approach
is critically a... | 9306219v1 |
1993-09-03 | Damping Rate of a Fermion in a Medium | We examine the relation between the damping rate of a massless, chiral
fermion that propagates in a medium, and the rate $\Gamma$ of approach to
equilibrium. It is proven that these quantities are equal, by showing that they
are given by the same formula in terms of the imaginary part of the self-energy
evaluated at th... | 9309225v2 |
1994-03-22 | On the Damping Rate of a Fast Fermion in Hot QED | The self-consistent determination of the damping rate of a fast moving
fermion in a hot QED plasma is reexamined. We argue how a detailed
investigation of the analytic properties of the retarded fermion Green's
function motivated by the cutting rules at finite temperature may resolve
ambiguities related to the proper d... | 9403335v1 |
1994-09-22 | Lyapunov Exponent and Plasmon Damping Rate in Nonabelian Gauge Theories | We explain why the maximal positive Lyapunov exponent of classical SU($N$)
gauge theory coincides with (twice) the damping rate of a plasmon at rest in
the leading order of thermal gauge theory. [This is a substantially revised and
expanded version of the manuscript.] | 9409392v2 |
1994-12-20 | Baryogenesis and damping in nonminimal electroweak models | We study the effect of damping on the generation of baryon asymmetry of the
Universe in the standard model of the eletroweak theory with simple extensions
of the Higgs sector. The propagation of quarks of masses up to about 5 GeV are
considered, taking into account their markedly different dispersion relations
due to i... | 9412330v1 |
1998-10-07 | Classical Kinetic Theory of Landau Damping for Self-interacting Scalar Fields in the Broken Phase | The classical kinetic theory of one-component self-interacting scalar fields
is formulated in the broken symmetry phase and applied to the phenomenon of
Landau damping. The domain of validity of the classical approach is found by
comparing with the result of a 1-loop quantum calculation. | 9810278v2 |
1999-08-02 | Plasma wave instabilities induced by neutrinos | Quantum field theory is applied to study the interaction of an electron
plasma with an intense neutrino flux. A connection is established between the
field theory results and classical kinetic theory. The dispersion relation and
damping rate of the plasma longitudinal waves are derived in the presence of
neutrinos. It ... | 9908206v2 |
1999-09-27 | Radiation Damping at a Bubble Wall | The first order phase transition proceeds via nucleation and growth of true
vacuum bubbles. When charged particles collide with the bubble they could
radiate electromagnetic wave. We show that, due to an energy loss of the
particles by the radiation, the damping pressure acting on the bubble wall
depends on the velocit... | 9909521v1 |
1999-10-08 | Lifetime of Collective Isospin Rotations of a Quantum Meson Field | We calculate the lifetime of the collective isospin rotating solutions which
have been found recently in the case a quantum N-component meson field with
exact O(N) symmetry. For this purpose we take into account the small breaking
of the O(N) symmetry associated to the non vanishing mass of the pion. This
term induces ... | 9910276v1 |
2000-02-08 | Finite pion width effects on the rho-meson and di-lepton spectra | Within a field theoretical model where all damping width effects are treated
self-consistently we study the changes of the spectral properties of rho-mesons
due to the finite damping width of the pions in dense hadronic matter at finite
temperature. The corresponding effects in the di-lepton yields are presented.
Some ... | 0002087v1 |
2000-08-31 | Damping of very soft moving quarks in high-temperature QCD | We determine the analytic expression of the damping rates for very soft
moving quarks in an expansion to second order in powers of their momentum in
the context of QCD at high temperature. The calculation is performed using the
hard-thermal-loop-summed perturbation scheme. We describe the range of validity
of the expan... | 0008335v1 |
2000-09-27 | Damping of the HERA effect in DIS? | The drastic rise of the proton structure function F_2(x,Q^2) when the
Bj\"orken variable x decreases, seen at HERA for a large span of Q^2, negative
values for the 4-momentum transfer, may be damped when Q^2 increases beyond
several hundreds GeV^2. A new data analysis and a comparison with recent models
for the proton ... | 0009313v2 |
2001-12-13 | Time evolution in linear response: Boltzmann equations and beyond | In this work a perturbative linear response analysis is performed for the
time evolution of the quasi-conserved charge of a scalar field. One can find
two regimes, one follows exponential damping, where the damping rate is shown
to come from quantum Boltzmann equations. The other regime (coming from
multiparticle cuts ... | 0112188v1 |
2002-04-26 | Oscillation damping of chiral string loops | Chiral cosmic string loop tends to the stationary (vorton) configuration due
to the energy loss into the gravitational and electromagnetic radiation. We
describe the asymptotic behaviour of near stationary chiral loops and their
fading to vortons. General limits on the gravitational and electromagnetic
energy losses by... | 0204304v1 |
2002-09-21 | Infrared Sensitivity in Damping Rate for Very Soft Moving Fermions in Finite Temperature QED | We calculate the fermion damping rate to second order in powers of the
external momentum $p$ in the context of QED at finite temperature using the
hard-thermal-loop (HTL) summation scheme. We find that the coefficient of order
$p^{2}$ is divergent in the infrared whereas the two others are finite. This
result suggests ... | 0209246v1 |
2005-11-22 | Ultrasoft Quark Damping in Hot QCD | We determine the quark damping rates in the context of next-to-leading order
hard-thermal-loop summed perturbation of high-temperature QCD where weak
coupling is assumed. The quarks are ultrasoft. Three types of divergent
behavior are encountered: infrared, light-cone and at specific points
determined by the gluon ener... | 0511258v1 |
2006-03-10 | Numerical Approach to Multi Dimensional Phase Transitions | We present an algorithm to analyze numerically the bounce solution of
first-order phase transitions. Our approach is well suited to treat phase
transitions with several fields. The algorithm consists of two parts. In the
first part the bounce solution without damping is determined, in which case
energy is conserved. In... | 0603081v2 |
1994-06-22 | Damped quantum harmonic oscillator: density operator and related quantities | A closed expression for the density operator of the damped harmonic
oscillator is extracted from the master equation based on the Lindblad theory
for open quantum systems. The entropy and effective temperature of the system
are subsequently calculated and their temporal behaviour is surveyed by showing
how these quanti... | 9406142v1 |
1997-05-09 | Radiation Damping of a BPS Monopole; an Implication to S-duality | The radiation reaction of a BPS monopole in the presence of incident
electromagnetic waves as well as massless Higgs waves is analyzed classically.
The reactive forces are compared to those of $W$ boson that is interpreted as a
dual partner of the BPS monopole. It is shown that the damping of acceleration
is dual to ea... | 9705059v2 |
1997-07-02 | The Asymptotic Method Developed from Weak Turbulent Theory and the Nonlinear Permeability and Damping Rate in QGP | With asymptotic method developed from weak turbulent theory, the kinetic
equations for QGP are expanded in fluctuation field potential $A^T_\mu $.
Considering the second-order and third-order currents, we derive the nonlinear
permeability tensor function from Yang-Mills field equation, and find that the
third-order cur... | 9707052v1 |
2005-04-07 | Continuous area spectrum in regular black hole | We investigate highly damped quasinormal modes of regular black hole coupled
to nonlinear electrodynamics. Using the WKB approximation combined with
complex-integration technique, we show that the real part of the frequency
disappears in the highly damped limit. If we use the Bohr's correspondence
principle, the area s... | 0504059v2 |
2005-05-16 | Supersymmetrization of the Radiation Damping | We construct a supersymmetrized version of the model to the radiation damping
\cite{03} introduced by the present authors \cite{ACWF}. We dicuss its
symmetries and the corresponding conserved Noether charges. It is shown this
supersymmetric version provides a supersymmetric generalization of the Galilei
algebra obtaine... | 0505142v1 |
1999-08-16 | Topological Entropy and epsilon-Entropy for Damped Hyperbolic Equations | We study damped hyperbolic equations on the infinite line. We show that on
the global attracting set $G$ the $\epsilon$-entropy (per unit length) exists
in the topology of $W^{1,\infty}$. We also show that the topological entropy
per unit length of $G$ exists. These results are shown using two main
techniques: Bounds i... | 9908080v1 |
2003-11-28 | Uniform stability of damped nonlinear vibrations of an elastic string | Here we are concerned about uniform stability of damped nonlinear transverse
vibrations of an elastic string fixed at its two ends. The vibrations governed
by nonlinear integro-differential equation of Kirchoff type, is shown to
possess energy uniformly bounded by exponentially decaying function of time.
The result is ... | 0311527v1 |
2005-07-06 | On stability and stabilization of elastic systems by time-variant feedback | We study a class of elastic systems described by a (hyperbolic) partial
differential equation. Our working example is the equation of a vibrating
string subject to linear disturbance. The main goal is to establish conditions
for stabilization and asymptotic stabilization by applying a fast oscillating
control to the st... | 0507123v1 |
2006-01-13 | Attractors for damped hyperbolic equations on arbitrary unbounded domains | We prove existence of global attractors for damped hyperbolic equations of
the form $$\aligned \eps u_{tt}+\alpha(x) u_t+\beta(x)u- \sum_{ij}(a_{ij}(x)
u_{x_j})_{x_i}&=f(x,u),\quad x\in \Omega, t\in[0,\infty[, u(x,t)&=0,\quad x\in
\partial \Omega, t\in[,\infty[.\endaligned$$ on an unbounded domain $\Omega$,
without smo... | 0601319v3 |
2007-02-07 | Finite time blow-up results for the damped wave equations with arbitrary initial energy in an inhomogeneous medium | In this paper we consider the long time behavior of solutions of the initial
value problem for the damped wave equation of the form \begin{eqnarray*}
u_{tt}-\rho(x)^{-1}\Delta u+u_t+m^2u=f(u) \end{eqnarray*} with some $\rho(x)$
and $f(u)$ on the whole space $\R^n$ ($n\geq 3$).
For the low initial energy case, which i... | 0702190v1 |
2007-03-09 | Analyticity and Riesz basis property of semigroups associated to damped vibrations | Second order equations of the form $z'' + A_0 z + D z'=0$ in an abstract
Hilbert space are considered. Such equations are often used as a model for
transverse motions of thin beams in the presence of damping. We derive various
properties of the operator matrix $A$ associated with the second order problem
above. We deve... | 0703247v1 |
2007-03-21 | Existence and asymptotic behavior of $C^1$ solutions to the multidimensional compressible Euler equations with damping | In this paper, the existence and asymptotic behavior of $C^1$ solutions to
the multidimensional compressible Euler equations with damping on the framework
of Besov space are considered. We weaken the regularity requirement of the
initial data, and improve the well-posedness results of Sideris-Thomases-Wang
(Comm.P.D.E.... | 0703621v1 |
2000-12-22 | The Vlasov-Poisson system with radiation damping | We set up and analyze a model of radiation damping within the framework of
continuum mechanics, inspired by a model of post-Newtonian hydrodynamics due to
Blanchet, Damour and Schaefer. In order to simplify the problem as much as
possible we replace the gravitational field by the electromagnetic field and
the fluid by ... | 0012041v1 |
2003-01-17 | Quantum mechanics of damped systems | We show that the quantization of a simple damped system leads to a
self-adjoint Hamiltonian with a family of complex generalized eigenvalues. It
turns out that they correspond to the poles of energy eigenvectors when
continued to the complex energy plane. Therefore, the corresponding generalized
eigenvectors may be int... | 0301024v3 |
2003-07-23 | Quantum Mechanics of Damped Systems II. Damping and Parabolic Potential Barrier | We investigate the resonant states for the parabolic potential barrier known
also as inverted or reversed oscillator. They correspond to the poles of
meromorphic continuation of the resolvent operator to the complex energy plane.
As a byproduct we establish an interesting relation between parabolic cylinder
functions (... | 0307047v1 |
2001-07-02 | Pattern formation and localization in the forced-damped FPU lattice | We study spatial pattern formation and energy localization in the dynamics of
an anharmonic chain with quadratic and quartic intersite potential subject to
an optical, sinusoidally oscillating field and a weak damping. The
zone-boundary mode is stable and locked to the driving field below a critical
forcing that we det... | 0107002v1 |
2003-06-16 | On the influence of noise on chaos in nearly Hamiltonian systems | The simultaneous influence of small damping and white noise on Hamiltonian
systems with chaotic motion is studied on the model of periodically kicked
rotor. In the region of parameters where damping alone turns the motion into
regular, the level of noise that can restore the chaos is studied. This
restoration is create... | 0306024v1 |
2003-07-30 | Faraday Wave Pattern Selection Via Multi-Frequency Forcing | We use symmetry considerations to investigate how damped modes affect pattern
selection in multi-frequency forced Faraday waves. We classify and tabulate the
most important damped modes and determine how the corresponding resonant triad
interactions depend on the forcing parameters. The relative phase of the
forcing te... | 0307056v1 |
2004-10-11 | Nodal two-dimensional solitons in nonlinear parametric resonance | The parametrically driven damped nonlinear Schr\"odinger equation serves as
an amplitude equation for a variety of resonantly forced oscillatory systems on
the plane. In this note, we consider its nodal soliton solutions. We show that
although the nodal solitons are stable against radially-symmetric perturbations
for s... | 0410012v1 |
2004-10-21 | Stabilization mechanism for two-dimensional solitons in nonlinear parametric resonance | We consider a simple model system supporting stable solitons in two
dimensions. The system is the parametrically driven damped nonlinear
Schr\"odinger equation, and the soliton stabilises for sufficiently strong
damping. The purpose of this note is to elucidate the stabilisation mechanism;
we do this by reducing the pa... | 0410044v1 |
2006-01-14 | Vibration of the Duffing Oscillator: Effect of Fractional Damping | We have applied the Melnikov criterion to examine a global homoclinic
bifurcation and transition to chaos in a case of the Duffing system with
nonlinear fractional damping and external excitation.
Using perturbation methods we have found a critical forcing amplitude above
which the system may behave chaotically.
Th... | 0601033v1 |
2006-10-22 | Response of a Magneto-Rheological Fluid Damper Subjected to Periodic Forcing in a High Frequency Limit | We explored vibrations of a single-degree of freedom oscillator with a
magneto-rheological damper subjected to kinematic excitations. Using fast and
slow scales decoupling procedure we derived an effective damping coefficient in
the limit of high frequency excitation. Damping characteristics, as functions
of velocity, ... | 0610055v1 |
2006-11-02 | Solitons in strongly driven discrete nonlinear Schrödinger-type models | Discrete solitons in the Ablowitz-Ladik (AL) and discrete nonlinear
Schr\"odinger (DNLS) equations with damping and strong rapid drive are
investigated. The averaged equations have the forms of the parametric AL and
DNLS equations. A new type of parametric bright discrete soliton and cnoidal
waves are found and the sta... | 0611004v1 |
1992-12-14 | Microscopic Origin of Quantum Chaos in Rotational Damping | The rotational spectrum of $^{168}$Yb is calculated diagonalizing different
effective interactions within the basis of unperturbed rotational bands
provided by the cranked shell model. A transition between order and chaos
taking place in the energy region between 1 and 2 MeV above the yrast line is
observed, associated... | 9212005v1 |
1996-12-17 | Damping mechanisms of the Delta resonance in nuclei | The damping mechanisms of the Delta(1232) resonance in nuclei are studied by
analyzing the quasi-free decay reactions 12C(pi+,pi+ p)11B and 12C(3He,t pi+
p)11B and the 2p emission reactions 12C(pi+,pp)10B and 12C(3He,t pp)10B. The
coincidence cross sections are calculated within the framework of the
isobar-hole model. ... | 9612046v1 |
1997-11-08 | Cooperative damping mechanism of the resonance in the nuclear photoabsorption | We propose a resonance damping mechanism to explain the disappearance of the
peaks around the position of the resonances higher than the $\Delta$ resonance
in the nuclear photoabsorption. This phenomenon is understood by taking into
account the cooperative effect of the collision broadening of $\Delta$ and
$N^{*}$, the... | 9711017v4 |
1998-05-27 | Collisional Damping of Nuclear Collective Vibrations in a Non-Markovian Transport Approach | A detailed derivation of the collisional widths of collective vibrations is
presented in both quantal and semi-classical frameworks by considering the
linearized limits of the extended TDHF and the BUU model with a non-Markovian
binary collision term. Damping widths of giant dipole and giant quadrupole
excitations are ... | 9805050v1 |
1999-07-06 | Probing the width of compound states with rotational gamma rays | The intrinsic width of (multiparticle-multihole) compound states is an
elusive quantity, of difficult direct access, as it is masked by damping
mechanisms which control the collective response of nuclei. Through microscopic
cranked shell model calculations, it is found that the strength function
associated with two-dim... | 9907016v1 |
1999-07-09 | Color plasma oscillation in strangelets | The dispersion relation and damping rate of longitudinal color plasmons in
finite strange quark matter (strangelets) are evaluated in the limits of weak
coupling, low temperature, and long wavelength. The property of the QCD vacuum
surrounding a strangelet makes the frequency of the plasmons nearly the same as
the colo... | 9907039v1 |
1999-09-21 | On the Collisional Damping of Giant Dipole Resonance | Collisional damping widths of giant dipole excitations are calculated in
Thomas-Fermi approximation by employing the microscopic in-medium
cross-sections of Li and Machleidt and the phenomenological Gogny force. The
results obtained in both calculations compare well, but account for about
25-35% of the observed widths ... | 9909057v1 |
2000-01-09 | Strongly damped nuclear collisions: zero or first sound ? | The relaxation of the collective quadrupole motion in the initial stage of a
central heavy ion collision at beam energies $E_{lab}=5\div20$ AMeV is studied
within a microscopic kinetic transport model. The damping rate is shown to be a
non-monotonic function of E_{lab} for a given pair of colliding nuclei. This
fact is... | 0001016v1 |
2002-11-18 | Collision damping in the pi 3He -> d'N reaction near the threshold | We present a simple quantum mechanical model exploiting the optical potential
approach for the description of collision damping in the reaction pi 3He -> d'N
near the threshold, which recently has been measured at TRIUMF. The influence
of the open d'N -> NNN channel is taken into account. It leads to a suppression
fact... | 0211050v1 |
2003-03-14 | Pion damping width from SU(2) x SU(2) NJL model | Within the framework of the NJL model, we investigate the modification of the
pion damping width in a hot pion gas for temperatures ranging from 0 to 180
MeV. The pion is found to broaden noticeably at T > 60 MeV. Near the chiral
phase transition T ~ 180 MeV, the pion width is saturated and amounts to 70
MeV. The main ... | 0303034v1 |
2004-06-09 | Damped collective motion of isolated many body systems within a variational approach to functional integrals | Two improvements with respect to previous formulations are presented for the
calculation of the partition function $\mathcal{Z}$ of small, isolated and
interacting many body systems. By including anharmonicities and employing a
variational approach quantum effects can be treated even at very low
temperatures. A method ... | 0406025v1 |
2004-07-26 | Damped collective motion of many body systems: A variational approach to the quantal decay rate | We address the problem of collective motion across a barrier like encountered
in fission. A formula for the quantal decay rate is derived which bases on a
recently developed variational approach for functional integrals. This formula
can be applied to low temperatures that have not been accessible within the
former PSP... | 0407092v2 |
1997-11-15 | Fluctuational phase-flip transitions in parametrically pumped oscillators | We analyze the rates of noise-induced transitions between period-two
attractors. The model investigated is an underdamped oscillator parametrically
driven by a field at nearly twice the oscillator eigenfrequency. The activation
energy of the transitions is analyzed as a function of the frequency detuning
and field ampl... | 9711014v1 |
1999-05-31 | Collisionless Damping of Low-Frequency Magnetosonic Pulses in a Two-Ion-Species Plasma | Low-frequency mangnetosonic pulses in a two-ion-species plasma are studied
theoretically and by simulation with a one-dimensional electromagnetic
simulation code based on a three-fluid model, with particular attention to the
dynamics of minority heavy ions. It is found that heavy ions can gain some
energy from the puls... | 9905059v1 |
2000-10-17 | Bunch Length Measurements at the ATF Damping Ring in April 2000 | This report presents bunch length and energy spread measurements performed in
April 2000 at the ATF Damping Ring, at KEK. Measurements were performed with
the beam on and then off the linear (difference) coupling resonance. Due to
strong intra-beam scattering in the ATF ring, the results depended strongly on
the coupli... | 0010043v1 |
2000-12-21 | Phase transition in the collisionless regime for wave-particle interaction | Gibbs statistical mechanics is derived for the Hamiltonian system coupling
self-consistently a wave to N particles. This identifies Landau damping with a
regime where a second order phase transition occurs. For nonequilibrium initial
data with warm particles, a critical initial wave intensity is found: above it,
thermo... | 0012053v1 |
2001-09-25 | Creep and Mechanical Oscillator Damping | Although "friction" is included in many models of oscillator damping,
including viscous ones applied to the pendulum; they "miss the mark" with
regard to a conceptual understanding of the mechanisms responsible for energy
loss. The theory of the present paper corrects some of these misunderstandings
by considering the ... | 0109067v1 |
2001-11-06 | Electromagnetic induction and damping - quantitative experiments using PC interface | A bar magnet, attached to an oscillating system, passes through a coil
periodically, generating a series of emf pulses. A novel method is described
for the quantitative verification of Faraday's law which eliminates all errors
associated with angular measurements, thereby revealing delicate features of
the underlying m... | 0111016v1 |
2003-08-31 | Effects of Bulk Viscosity in Non-linear Bubble Dynamics | The non-linear bubble dynamics equations in a compressible liquid have been
modified considering the effects of compressibility of both the liquid and the
gas at the bubble interface. A new bubble boundary equation has been derived,
which includes a new term resulted from the liquid bulk viscosity effects. The
influenc... | 0309012v1 |
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