Radiation by relativistic dipoles. II

In a continuation of an earlier study, the electromagnetic fields of a point magnetic moment — a magneton — in uniform rectilinear motion, with a given spin precession, are analyzed. It is shown that the same equations can be found through Lorentz transformations from the corresponding expressions in the rest frame. The relationship between the electric and magnetic fieldsE andH radiated by a point magnetic dipole moment and a point electric dipole moment is derived through the use of dual transformations of the electromagnetic field tensor. It is assumed that each moment is in relativistic and otherwise arbitrary motion. In the relativistic case, as in the nonrelativistic case, the switch is accompanied by the replacementsHE, E-H. A covariant formalism is developed for describing the electromagnetic fields in the wave zone. The electromagnetic field tensor associated with the radiation is analyzed.V. V. Kuibyshev Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 73–78, March, 1993.     

Radiation by relativistic dipoles. IV

An analysis is made of radiation emitted by a neutron moving in constant and homogeneous electromagnetic fields (EH whereE=H, andEH whereEH) as a supplement to the classical theory of radiation from a point magnetic moment (a magneton) developed by the authors. The results obtained are found to be in agreement with the radiation theory of Ternov, Bagrov, and others constructed on the basis of the Dirac-Pauli equation. A study is made of the spectral composition and the invariance properties of the total radiation power.Tomsk University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 63–71, February, 1995.     

Radiation by relativistic dipoles. III

The classical radiation of a point magnetic moment (a magneton) moving at a constant velocity in an arbitrary direction with respect to the field lines of a uniform magnetic field is analyzed. All characteristics of the radiation agree with the Ternov-Bagrov-Khapaev relativistic quantum thoery of the radiation by a neutron. It is thus demonstrated that the classical model of radiation with spin flip is valid. The correspondence principle in the theory of radiation with spin flip will be discussed in more detail in subsequent papers.V. V. Kuibyshev Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 53–59, January 1994.     

Radiation of relativistic dipoles. I

In the proposed series of articles, a systematic exposition will be given of the classical theory of radiation of relativistic point dipoles. Specific examples of radiation having practical significance will also be considered. V. V. Kuibyshev Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 60–64, February, 1993.     

Radiation of a relativistic magneton. III

An expression is given for the angular distribution of the change in the four-dimensional momentum of the radiation of a charged magneton in unit proper time. The expression is given for both the tensor and the vector form of expression of the intrinsic magnetic moment. A method of covariant integration of the angular distribution of the radiation in the laboratory coordinate system is developed. The results of the integration in the tensor and vector variants go over into each other exactly.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 33–38, October, 1980.     

Radiation of a relativistic magneton. II

Some general properties of the radiation of a magneton in arbitrary motion are studied. As an example, an investigation is made into the radiation of a uniformly and rectilinearly moving magneton whose magnetic moment processes at a constant frequency in the plane perpendicular to the motion. It is shown that the fundamental frequency, shifted by the relativistic Doppler effect is radiated. The angular distribution and the linear and circular polarizations of the radiation are found. The conclusions agree with the quantum theory of the radiation of a magnetic moment.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 108–111, May, 1980.We thank Professor V. G. Bagrov for fruitful discussion of the results of this paper.     

Radiation of a relativistic magneton. I

A derivation is given of the field intensities created in vacuum by a neutral, arbitrarily moving point particle possessing a proper magnetic moment. For brevity this particle is called a magneton. The field of the magneton is represented as the superposition of a convective field and a radiation field. It is shown that the radiation field possesses the characteristic properties of the field of an electromagnetic plane wave — orthogonality and transversality.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 12–16, May, 1978.The authors wish to thank Professor V. G. Bagrov for his interest in the work and for valuable remarks.     

Radiation of a relativistic rotator

The spectrum and total radiation intensity of a relativistic cylindrical rotator, including the polarization and spin characteristics, are obtained. Cases of small and large values of the parameter ξ = (3/2)(?/mcR) (E/mc²)² are considered, where E is the energy and R is the radius of the electron orbit.     

Radiation of systems with relativistic electrons

Different methods of generating electromagnetic radiation in connection with the motion of electrons in external electromagnetic fields are discussed in this paper.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 5–31, February, 1980.     

Radiation of relativistic electrons in a variable undulator

A study is made of the polarization, spectral, and angular characteristics of the radiation of an electron in an arbitrary system of constant undulators with different strengths, distributions, periods, and number of periods of the magnetic field. It is shown that such a system enables one to obtain any form of the radiation spectrum in a wide range of wavelengths.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 48–51, June, 1977.     

Radiation of relativistic electrons in a magnetic undulator

Expressions are obtained for the spectral-angular characteristics of the radiation in two limiting cases: 1 and 1 ( is the angle of deflection of the electron in the field, and is the energy of the electron in units of mc²). It is shown that in the latter case the maximum of the radiation occurs at higher harmonics.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 88–91, October, 1973.In conclusion the authors thank Professor A. A. Sokolov for useful discussions.     

Radiation from relativistic positrons channeled in single crystals

The characteristic of the radiation emitted from relativistic positrons channelled between the major planes in single crystal have been calculated. The sharp peaks of the emission spectrum in the keV region is predicted correctly and is compared with previous calculations.     

Radiation of tangential dipoles at the boundary of semiinfinite planar impedance systems

A factorization method is used to solve a group of electrodynamic problems involving the radiation of dipoles at a straight discontinuity in the surface impedance specified on an infinite plane and at the edge of an impedance halfplane tangential to these systems.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, Vol. 12, No. 4, pp. 50–55, April, 1969.     

Modeling trajectories and radiation spectra of relativistic particles in crystals. Radiation polarization characteristics

A method is developed for calculation of the polarization characteristics of radiation based on computer tracking of relativistic particle trajectories. The dependence of the Stokes parameter which defines the polarization properties of the radiation upon photon frequency is determined for characteristic trajectories. Formation of full spectra and the degree of linear polarization for averaging over possible trajectories are considered, and results are compared with available experiments.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 63–68, November, 1986.The authors are indebted to S. A. Vorob'ev for his support in the study and evaluation, to M. I. Podgoretskii and A. P. Potyltsyn for their valuable discussion, and to O. V. Boyarko for assistance in formulating the plan of the study.