Entity

Time filter

Source Type

Leninaul, Russia

Lebedev S.L.,Surgut State University
International Journal of Modern Physics A | Year: 2014

The radiation processes emerging as a result of interaction between spin and orbit degrees of freedom of spinning charge are investigated with the use of the Bargmann-Michel-Telegdi (BMT) model. The spin contribution to the self-energy of the ultrarelativistic particle is imaginary and proportional to invariant constructed from the derivatives of the worldline and from the spin. This invariant determines up to negative numerical factor of the QED spin contribution to the imaginary part of the mass shift (MS). Particular cases of crossed, electric and magnetic external fields are considered in detail. The influence of an ideal boundary upon the self-energy of the particle is analyzed for the crossed field case. In the presence of the "mirror" the imaginary part of the MS gets an addition and the nonzero spin dependent real part appears, both however giving the small corrections to no-boundary MS. An alternative method to obtain the spin magnetic moment correction to the power of synchrotron radiation entails in generalization of the result known for the planar motion. Special attention is given to disagreement between classical and quantum pictures of spin radiation. © 2014 World Scientific Publishing Company. Source


Lebedev S.L.,Surgut State University
Journal of Experimental and Theoretical Physics | Year: 2016

Spin radiative effects in a one-particle sector of QED have a dual nature and can be understood with the Frenkel classical rotating-electron model. In the region of parameters under study γ⊥ 2 ≫ 1 (γ⊥ 2 = 1 + p⊥ 2/m2) and χ ≪ 1 (χ = √(eFµvpv)2/m3), the imaginary part of the mass shift and radiation power contain two types of spin contributions. The contributions of the first type are related to the intrinsic magnetic moment of a fermion representing an additional source of electromagnetic radiation. The contributions of the second type have the opposite sign and are caused by a small change in the electron acceleration appearing due to the Frenkel addition to the particle mass. Contributions of the second type dominate, which explains the “wrong” sign of total spin corrections. We show that not only the sign but also the values of coefficients can be explained with specified accuracy using classical electrodynamics if corrections to the mass shift (action) and radiation power are calculated in canonical variables, i.e., for fixed velocity and momentum values, respectively. The results can be treated as a demonstration of the correspondence principle in the field of radiative spin effects, in addition to correspondence between classical and quantum theories at the tree (in the external filed) level. For ae ≡ (g–2)/2 ≲ χ ≪ 1, equations of the Frenkel model lead to generalization of the system of Lorentz–BMT (Bargmann–Michel–Telegdi) equations taking into account the Frenkel addition to mass. Some features of experimental observations of the spin light are discussed. © 2016, Pleiades Publishing, Inc. Source


Karpin V.A.,Surgut State University
Human Ecology | Year: 2014

In recent decades, great achievements in the field of geology, astronomy and cosmology attracted attention of the scientific community to study of biotropic effects of heliogeophysical factors, especially to different anomalies of natural magnetic fields. A new branch in science - magnetic biology has appeared. Several strategic directions in study of magnetic biological effects have been outlined so far: importance of natural magnetic anomalies in complex biotropic impact of various adverse ecological factors on human body; interrelation of heliogeomagnetic activity with climatic elements of regions; study of features of magnetic biological effects in the territory of the northern latitudes where biogenic effects of heliogeomagnetic anomalies are most vivid. The obtained results necessitate the need of a wider research of heliogeophysical factors' risk for population health in the northern urban territories. Source


It is found means of X-ray structural analysis, transmission electron microscopy, scanning electron microscopy combined with electron backscatter diffraction, and optical metallography that the reduction of the integral magnitude of the long-range atomic order in Ni3Mn and Pd3Fe L12-superstucture alloys ordered through the A1 + L12two-phase region is accompanied by antiphase domains coarsening and grains fining. © Allerton Press, Inc., 2014. Source


Nenashev A.V.,Surgut State University
Radioelectronics and Communications Systems | Year: 2014

The problem of simulation of nonlinear radio engineering devices is considered on the basis of the functional analysis theory. It has been shown that in particular cases such approach results in known techniques of harmonic balance and Volterra series. The new algorithm, which has better computing characteristics compared with techniques of harmonic balance and of Krylov subspaces, has been developed. © 2014, Allerton Press, Inc. Source

Discover hidden collaborations