Dynamically stable electron bunches in beam interaction with an electromagnetic wave packet

Nonlinear interaction of electron beam with a whistler wave packet that effectively dissipates through collisions or wave leakage is studied. Independently of the dissipation type and nature of waves, self-organization of the beam structure leads to the formation of bunches continuously decelerated by waves. Strong dissipation prevents phase mixing required for the quasilinear theory and keeps wave phases in the packet correlated. Thus, dynamically stable bunches are present together with a plateau in the velocity distribution; asymptotically, wave emission by bunches is the main process.     

Electron spin precession in the field of an electromagnetic wave

The solution of the Dirac equation for an electron in the field of a plane circularly polarized electromagnetic wave having an arbitrary intensity and a phase velocity v _ph different from the speed of light c is obtained. This solution is shown to describe the previously unknown effect of electron spin precession that exceeds the known precession effects caused by radiative corrections by six and more orders of magnitude and opens new possibilities for control of the polarization of electrons and for realization of various resonance methods associated with the spin precession. The predicted effect is in agreement with symmetry principles; however, it disappears at v _ph=c and is not described by the known Volkov solution.     

Motion of a particle in a static magnetic field and in the field of a electromagnetic plane wave

The solutions of the equations of motion of a charged particle in an external electromagnetic field consisting of a superposition of a constant uniform magnetic field and the field of a circularly polarized electromagnetic plane wave are presented as solutions of the Cauchy problem. The resonance case is studied. Zh. Tekh. Fiz. 67, 94–99 (February 1997)     

Motion and radiation of an electron exhibiting a vacuum magnetic moment in the field of a plane electromagnetic wave

A study is made of the motion of an electron exhibiting an anomalous magnetic moment and moving in the field of a plane circularly polarized electromagnetic wave. An exact solution is found to the generalized Dirac equation and is utilized to study the emission of electromagnetic radiation from the electron (the Compton effect). It is shown that allowance for the anomalous magnetic moment of the electron leads to: a frequency shift, a change in the total radiated power, polarization of the radiation, and to spin effects.     

Motion of a particle in a static magnetic field and the field of a monochromatic electromagnetic plane wave

A solution of the equation of motion of a charged particle in an external electromagnetic field comprising a superposition of a uniform static magnetic field and the field of a monochromatic, elliptically polarized electromagnetic plane wave is obtained as the solution of a Cauchy problem. The resonance case is investigated. An analysis of the resulting solution is given. Zh. Tekh. Fiz. 69, 106–110 (May 1999)     

Charge symmetry of wave functions for an electron in a quantized electromagnetic wave field

The violation of charge symmetry in the known [1] wave functions for an electron in a quantized wave field is considered. An attempt is made to modify the equations and to construct solutions free of this deficiency.     

Vacuum pair-production in a classical electric field and an electromagnetic wave

Using semiclassical WKB-methods, we calculate the rate of electron–positron pair-production from the vacuum in the presence of two external fields, a strong (space- or time-dependent) classical field and a monochromatic electromagnetic wave. We discuss the possible medium effects on the rate in the presence of thermal electrons, bosons, and neutral plasma of electrons and protons at a given temperature and chemical potential. Using our rate formula, we calculate the rate enhancement due to a laser beam, and discuss the possibility that a significant enhancement may appear in a plasma of electrons and protons with self-focusing properties.     

Motion of trapped electrons in gyro-resonant electromagnetic field

It is shown that the phase space of magnetically trapped electrons in plasmas interacting with gyro-resonant electromagnetic waves is divided into two parts. In one, as a particle gains energy its turning point moves towards the region of weaker magnetic field; in the other, energy gain results in the turning point moving towards the region of stronger magnetic field, with possible detrapping.     

Evolution of the width of the wave packet of a charged particle interacting with a quantum electromagnetic field

The path integral method is used to study the width of the wave packet of a relativistic charged particle interacting with a quantum electromagnetic field. A general expression is derived for the density distribution of a particle moving in arbitrary external potentials. An electron synchrotron with weak focusing is studied as a specific example, and the width of the wave packet of an electron moving in this accelerator is found. Zh. éksp. Teor. Fiz. 111, 1563–1578 (May 1997)     

Motion of a classical charged particle with spin in the external field of a plane electromagnetic wave

We obtain the solution to the equations of motion for a classical particle with spin, electric and magnetic charges, and electric and magnetic normal and anomalous moments, in the field of a plane electromagnetic wave. An explicit form of the solution is given for linearly polarized waves and monochromatic circularly polarized waves. The possibility is noted that due to the presence of the moments, the particle can be accelerated to speeds arbitrarily close to the speed of light.Translated from Izvestiya Vysshykh Uchebnykh Zavedenii, Fizika, No. 11, pp. 71–74, November, 1981.     

Spectrum and polarization of electrons in neutron beta-decay in an electromagnetic wave field

A study is made on a polarized neutron undergoing -decay induced by an intense electromagnetic wave. The angular distribution of electrons in the decay is obtained and their polarization is studied. A comparison is made with the decay of a moving neutron.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 33–37, March, 1987.The authors are grateful to L. I. Lapidus, B. K. Kerimov, and G. A. Chizhov for their interest in this work and for their constructive criticism.     

Radiation of an electron in the quantum field of a nonmonochromatic electromagnetic wave

This study considers the radiation of an electron upon its interaction with one photon and a vacuum of all remaining photons of a quantum plane nonmonochromatic electromagnetic wave. Consideration of the vacuum of an infinite number of photons leads to a change in the spectrum and differential probability of radiation. In the case of a low-intensity plane wave the corresponding finite corrections are calculated, reflecting the role of the vacuum in the process under consideration.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 120–127, July, 1978.The authors thank V. G. Bagrov and D. M. Gitman for their valuable advice on the questions considered in this study.     

Motion of an ideal fluid in the field of a plane gravitational wave

An exact solution of the equations of relativistic hydrodynamics is found which describes the motion of an initially uniform ideal fluid in the field of a plane gravitational wave of arbitrary amplitude and polarization. For all solutions we find that the pressure and energy density develop singularities on the singular surface, and the velocity of the fluid in the direction of propagation of the gravitational wave approaches the speed of light. In the case of the equation of state =p, the solution becomes intrinsically unstable and describes the generation of sound waves.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 96–99, November, 1982.