On nonlinear nonlocal equations in wave theory. Part I: the Whitham equation
On nonlinear nonlocal equations in wave theory. Part I: the Whitham equation
P.I. Naumkin, I.A. Shishmarev
Physical problems involving nonlinear nonlocal equations (NNE) have been reviewed. The topics discussed included (i) local and global existence in time of solutions to nonlinear nonlocal equations, (ii) breaking of solutions in a finite time interval, (iii) estimation of the time of existence of solutions, (iv) smoothing of discontinuous initial perturbations with time, and (v) construction of generalized solutions.
Show AbstractOn deformation of the Debye charge screening sphere
On deformation of the Debye charge screening sphere
A.S. Vshivtsev, V.Ch. Zhukovskii, B.V. Magnitskii, A.V. Tatarintsev
The field and temperature corrections to the photon polarization operator in an external magnetic field have been studied for different limiting values of photon momentum, magnetic field strength, and temperature. Consideration is given to the deformation of the Debye charge screening sphere jin a magnetic field.
Show AbstractAxigluonic decay of toponium
Axigluonic decay of toponium
R.N. Faustov, I.G. Vasilevskaya
The chiral color model predicts the existence of axigluons, a color octet of massive axial-vector gauge bosons. In this connection of interest is the toponium decomposition into axigluons and gluons. In this paper the following types of toponium decay are considered: $\theta \to Ag$, $\theta \to AAg$, and $\theta \to ggg \to AAg$. The decay widths of toponium $S$ states are calculated for various possible values of the axigluon mass.
Show AbstractThe effect of dissipation in a Kerr medium on the error of wave energy measurements
The effect of dissipation in a Kerr medium on the error of wave energy measurements
Yu.I. Vorontsov
In quasi-nonperturbing measurements of wave energy, dissipation due to wave interaction in a Kerr medium is shown to restrict the error of determining the number $N$ of quanta to a value of $\sqrt{Nq}$ ($q$ is the absorption coefficient). Self-action of the wave and its dissipation determine the optimum power of the probing wave and the interaction length.
Show AbstractExcitation of eddy fields in periodic waveguides by a high-intensity electron beam
Excitation of eddy fields in periodic waveguides by a high-intensity electron beam
V.I. Kanavets, A.S. Nifanov, A.I. Slepkov
A method is worked out for analyzing a self-consistent interaction on of a linear electron beam with fields in a multimode periodic waveguide used in relativistic microwave electronics. Investigation of a finite length system showed that at the waveguide surface there is an eddy field corresponding to the surface wave. The electron beam generates entrained fields with a maximum strength in the beam region. Scattering of the surface wave field and the electron beam field by the system inhomogeneities results in the production of a high-power circumaxial radiation.
Show AbstractQuantum nondemolition measurement of photon energy in the quadratic electron scattering scheme
Quantum nondemolition measurement of photon energy in the quadratic electron scattering scheme
S.P. Vyatchanin
An electron traveling along a bare dielectric waveguide at a velocity near the phase velocity acquires a transverse momentum proportional to the photon energy. It is proposed that this momenjtum be measured. The effect is analyzed with consideration for the waveguide dispersion, radiation friction and the spurious Cerenkov radiation. Use should be made of a corrugated-wall waveguide to eliminate the Cerenkov emission and to derive the required frequency dependence of the phase velocity.
Show AbstractSimulation of energy migration processes in a photosynthetic unit as dependent on the number of spectral forms of Chlorophyll a and the spatial arrangement of pigment molecules
Simulation of energy migration processes in a photosynthetic unit as dependent on the number of spectral forms of Chlorophyll a and the spatial arrangement of pigment molecules
A.A. Demidov, E.A. Chernyavskaya
The effect of the structural organization on the energy migration efficiency in a light-collecting antenna (LCA) has been studied by numerical modeling. It is concluded that for an ordered mutual arrangement of Chlorophyll a molecules in an LCA, the rate of energy migration along the photosynthetic unit antenna can markedly exceed that for a random arrangement of the pigment molecules.
Show AbstractThin-layer interference structures with a three-layer period
Thin-layer interference structures with a three-layer period
A.V. Kozar', E.L. Ryazanova
A theoretical and numerical analysis of the basic optical and structural properties of thin-layer (the total optical thickness below the quarter-wave) antireflecting structures with a three-layer period has shown that these structures can exert anti-reflecting effects simultaneously in two media with different refractive indexes. Simple analytical relations have been obtained which allow synthesis of such multilayer structures in order to solve various problems of applied optics.
Show AbstractNonlinear evolution of quasicircular flows: Burgers models and acousto-hydrodynamic analogy
Nonlinear evolution of quasicircular flows: Burgers models and acousto-hydrodynamic analogy
Yu.N. Makov, O.V. Rudenko
The nonlinear evolution of two-dimensional flows with flow lines represented by angle-modulated circles has been considered for an ideal fluid. To solve the problem, an approximate Burgers equation has Ьеец derived for the flow function and analogies with wave problems of nonlinear acbustics have been used.
Show AbstractMeasurement of the ground reflectivity in shallow sea using a pressure-gradient transducer
Measurement of the ground reflectivity in shallow sea using a pressure-gradient transducer
B.I. Goncharenko, V.A. Gordienko, E.O. Ermolaeva
Methods of studying the ground reflectivity in the low-frequency range with the help of combined receiving devices are discussed. The value of the acoustic bottom reflectivity obtained by forming unidirectional characteristics of the receiving system is compared with that measured by the interference technique. It is noted that the measurement error can be decreased by a simultaneous use of data on the pressure field sections and the vertical component of the oscillatory velocity field.
Show Abstract