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1.
Amos Harpaz 《International Journal of Theoretical Physics》2007,46(3):430-436
The role of the characteristic length that characterizes linear acceleration is studied, in order to find how does this length
determine the characteristic wavelength of the radiation created by the accelerated charge. Unruh equation for the temperature
observed by a detector accelerated relative to the vacuum is used to determine the wavelength distribution of the radiation
emitted by a linearly accelerated charge, and it is found that this distribution is peaked close to the characteristic length
that characterizes the linear acceleration, which is the radius of curvature of the curved electric field created by the acelerated
charge.
PACS numbers: 11.10; 41.60.m. 相似文献
2.
G. G. Karapetyan 《Technical Physics》1997,42(11):1349-1350
Small oscillations of the charge in a rectangular waveguide are considered. The electromagnetic field generated by these oscillations
and its effect on the charge are investigated. It is found that at a certain frequency there is a self-consistent regime of
oscillations wherein the charge oscillates under the influence of its self-field in the absence of external forces. The combination
of such a charge and the self-consistent alternating field has the property of a quasiparticle, which is named an electromagneton.
Zh. Tekh. Fiz. 67, 120–121 (November 1997) 相似文献
3.
We examine whether a charge supported statically in a gravitational field radiates, and find the answer to this question to be positive. Based on our earlier results we find that the important condition for the creation of radiation is the existence of a relative acceleration between the charge and its electric field, where such an acceleration causes the curving of the electric field and the creation of a stress force due to this curvature. This stress force is the reaction force, which creates the radiation. Later we find that this condition do exist for a charge supported statically in a gravitational field, where the electric field of the charge falls in the gravitational field, it curves, and the stress force raised in this curved field, creates electromagnetic radiation. 相似文献
4.
The Vavilov-Cherenkov radiation appearing in a circular regular ideal waveguide with a chiral medium is considered. The features
of the emission spectrum excited by a charge moving along the waveguide axis are investigated. Expressions for the energy
loss of a moving charge are obtained.
Zh. Tekh. Fiz. 69, 69–71 (March 1999) 相似文献
5.
The emission of radiation by a uniformly accelerated charge is analyzed. According to the standard approach, a radiation is observed whenever there is a relative acceleration between the charge and the observer. Analyzing difficulties that arose in the standard approach, we propose that a radiation is created whenever a relative acceleration between the charge and its own electric field exists. The electric field induced by a charge accelerated by an external (nongravitational) force is not accelerated with the charge. Hence the electric field is curved in the instantaneous rest frame of the accelerated charge. This curvature gives rise to a stress force, and the work done to overcome the stress force is the source of the energy carried by the radiation. In this way, the energy balance paradox finds its solution. 相似文献
6.
Abstract Radiation generated by relativistic charges can be analyzed and described in exquisite detail. One reason that such detailed analysis is possible is because the phases of radiated photons often are determined completely by the initial conditions of the relativistic charges and the radiating system. The phase relationships between the initial charges and the radiated photons represent coherence in the emitted radiation. A previous paper decribed how this coherence could affect the spatial and spectral distributions of radiation generated by a single charge in a periodic radiator. The present paper discusses a complementary issue; namely, how the temporal shape of a relativistic charge bunch can emphasize specific features of the radiation generated at a single interaction site. 相似文献
7.
Experimental investigations and theoretical-model analyses have been made of the magnetooptic diffraction of light at ferrite
garnet magnetic films with a banded domain structure which includes isolated magnetic grating defects in the form of “forks”
and “breaks.” An analysis of the magnetic grating structure and the light diffraction field shows that in terms of its action
on laser radiation, a banded domain grating is similar to a computer-synthesized phase hologram of an isolated pure screw-wavefront
dislocation. It is shown that as a result of magnetooptic diffraction at a magnetic hologram, optical vortices may be reconstructed
with a helicoidal wavefront carrying the topological charge l=±1,±2.
Zh. Tekh. Fiz. 68, 54–58 (December 1998) 相似文献
8.
Timothy H. Boyer 《Foundations of Physics》2002,32(1):1-39
A fundamentally new understanding of the classical electromagnetic interaction of a point charge and a magnetic dipole moment through order v
2
/c
2
is suggested. This relativistic analysis connects together hidden momentum in magnets, Solem's strange polarization of the classical hydrogen atom, and the Aharonov–Bohm phase shift. First we review the predictions following from the traditional particle-on-a-frictionless-rigid-ring model for a magnetic moment. This model, which is not relativistic to order v
2
/c
2
, does reveal a connection between the electric field of the point charge and hidden momentum in the magnetic moment; however, the electric field back at the point charge due to the Faraday-induced changing magnetic moment is of order 1/c
4
and hence is negligible in a 1/c
2
analysis. Next we use a relativistic magnetic moment model consisting of many superimposed classical hydrogen atoms (and anti-atoms) interacting through the Darwin Lagrangian with an external charge but not with each other. The analysis of Solem regarding the strange polarization of the classical hydrogen atom is seen to give a fundamentally different mechanism for the electric field of the passing charge to change the magnetic moment. The changing magnetic moment leads to an electric force back at the point charge which (i) is of order 1/c
2
, (ii) depends upon the magnetic dipole moment, changing sign with the dipole moment, (iii) is odd in the charge q of the passing charge, and (iv) reverses sign for charges passing on opposite sides of the magnetic moment. Using the insight gained from this relativistic model and the analogy of a point charge outside a conductor, we suggest that a realistic multi-particle magnetic moment involves a changing magnetic moment which keeps the electromagnetic field momentum constant. This means also that the magnetic moment does not allow a significant shift in its internal center of energy. This criterion also implies that the Lorentz forces on the charged particle and on the point charge are equal and opposite and that the center of energy of each moves according to Newton's second law F=Ma where F is exactly the Lorentz force. Finally, we note that the results and suggestion given here are precisely what are needed to explain both the Aharonov–Bohm phase shift and the Aharonov–Casher phase shift as arising from classical electromagnetic forces. Such an explanation reinstates the traditional semiclassical connection between classical and quantum phenomena for magnetic moment systems. 相似文献
9.
GODEHARD SUTMANN 《Molecular physics》2013,111(12):1781-1788
For the calculation of ε(k) via the correlation function of the bound charge density fluctuations or the ratio of the bound charge density to an external charge density, a generalized form of the fluctuation dissipation theorem is derived which accounts for different types of boundary conditions through a modified Green's function. It is demonstrated for the case of an interaction site model of water that it is possible to obtain consistent results for the non-local dielectric function with different types of boundary conditions. This is shown by calculating ε(k) both from the correlation function 〈ρb(k)ρb(-k)〉 and from the dielectric response to an external electric field. 相似文献
10.
D. V. Karlovets 《Journal of Experimental and Theoretical Physics》2011,113(1):27-45
Polarization radiation generated when a point charge moves uniformly along a straight line in vacuum in the vicinity of media
with a finite permittivity ɛ(ω) = ɛ′ + iɛ″ and sharp boundaries is considered. A method is developed in which polarization radiation is represented as the field of
the current induced in the substance by the field of the moving charge. The solution to the problem of radiation induced when
a charge moves along the axis of a cylindrical vacuum channel in a thin screen with a finite radius and a finite permittivity
is obtained. Depending on the parameters of the problem, this solution describes various types of radiation (Cherenkov, transition,
and diffraction radiation). In particular, when the channel radius tends to zero and the outer radius of the screen tends
to infinity, the expression derived for the emitted energy coincides with the known solution for transition radiation in a
plate. In another particular case of ideal conductivity (ɛ″ → ∞), the relevant formula coincides with the known results for
diffraction radiation from a circular aperture in an infinitely thin screen. The solution is obtained to the problem of radiation
generated when the charge flies near a thin rectangular screen with a finite permittivity. This solution describes the diffraction
and Cherenkov mechanisms of radiation and takes into account possible multiple re-reflections of radiation in the screen.
The solution to the problem of radiation generated when a particles flies near a thin grating consisting of a finite number
of strips having a rectangular cross section and a finite permittivity and separated by vacuum gaps (Smith-Purcell radiation)
is also obtained. In the special case of ideal conductivity, the expression derived for the emitted energy coincides with
the known result in the model of surface currents. 相似文献
11.
The conditions in which electromagnetic radiation is formed are discussed. It is found that the main condition for the emission of radiation by an electric charge is the existence of a relative acceleration between the charge and its electric field. Such a situation exists both for a charge accelerated in a free space, and for a charge supported at rest in a gravitational field. Hence, in such situations, the charges radiate. It is also shown that relating radiation to the relative acceleration between a charge and its electric field, solves several difficulties that existed in earlier approaches, like the energy balance paradox, and the relativistic nature of the observation of the emitted radiation. 相似文献
12.
P. K. Anastasovski T. E. Bearden C. Ciubotariu W. T. Coffey L. B. Crowell G. J. Evans M. W. Evans R. Flower S. Jeffers A. Labounsky B. Lehnert M. Mészáros P. R. Molnar S. Roy J. P. Vigier 《Foundations of Physics Letters》2002,15(6):561-568
The Aharonov-Bohm effect shows that the vacuum is structured, and that there can exist a finite vector potentialA in the vacuum when the electric field strengthE and magnetic flux densityB are zero. It is shown on this basis that gauge theory produces energy inherent in the vacuum. The latter is considered as
the internal space of the gauge theory, containing a field made up of components ofA, to which a local gauge transformation is applied to produce the electromagnetic field tensor, a vacuum charge/current density,
and a topological charge g. Local gauge transformation is the result of special relativity and introduces spacetime curvature,
which gives rise to an electromagnetic field whose source is a vacuum charge current density made up ofA and g. The field carries energy to a device which can in principle extract energy from the vacuum. The development is given
forU(1) andO(3) invariant gauge theory applied to electrodynamics.
Former Edward Davies Chemical Laboratories, University College of Wales, Aberystwyth SY32 1NE, Wales, United Kingdom. 相似文献
13.
M. W. Evans 《Foundations of Physics Letters》1994,7(6):577-583
By solving the Diras equation for the motion of an electron (c) in the circularly polarized electromagnetic field it is shown that the intrinsic electron spin forms an interaction Hamiltonian with a time independent fieldB
(3) of electromagnetic radiation in the vacuum. In the same way as intrinsic spin is a fundamental property of the electron,B
(3) is therefore a fundamental and intrinsic property of the vacuum electromagnetic field. 相似文献
14.
高能带电粒子与航天器介质材料相互作用引起的深层带电现象, 一直是威胁航天器安全运行的重要因素之一. 考虑入射电子在介质中的电荷沉积、能量沉积分布以及介质中的非线性暗电导和辐射诱导电导, 建立了介质深层充电的单极性电荷输运物理模型. 通过求解电荷连续性方程和泊松方程, 可以得出不同能量 (0.1–0.5 MeV) 电子辐射下, 低密度聚乙烯 (厚度为1 mm) 介质中的电荷输运特性. 计算结果表明, 不同能量的电子辐射下, 介质充电达到平衡时, 最大电场随入射能量的增加而减小; 同一能量辐射下, 最大电场随束流密度的增大而增加. 入射电子能量较低时 (≤ 0.3 MeV) , 最大电场随束流密度的变化趋势基本相同. 具体表现为: 当束流密度大于3× 10-9 A/m2时, 最大场强超过击穿阈值2×107 V/m, 发生静电放电 (ESD) 的可能性较大. 随着入射电子能量的增加, 发生静电放电 (ESD) 的临界束流密度增大, 在能量为0.4 MeV时, 临界束流密度为6×10-8 A/m2. 当能量大于等于0.5 MeV时, 在束流密度为10-9–10-6 A/m2的范围内, 均不会发生静电放电 (ESD) . 该物理模型对于深入研究深层充放电效应、评估航天器在空间环境下 深层带电程度及防护设计具有重要的意义.
关键词:
高能电子辐射
低密度聚乙烯(LDPE)
介质深层充电
电导特性 相似文献
15.
16.
Spectral Analysis for Systems of Atoms and Molecules Coupled to the Quantized Radiation Field 总被引:2,自引:2,他引:0
Volker Bach Jürg Fröhlich Israel Michael Sigal 《Communications in Mathematical Physics》1999,201(2):249-290
We consider systems of static nuclei and electrons – atoms and molecules – coupled to the quantized radiation field. The interactions
between electrons and the soft modes of the quantized electromagnetic field are described by minimal coupling, p→p−e
A (x), where A(x) is the electromagnetic vector potential with an ultraviolet cutoff. If the interactions between the electrons and the quantized
radiation field are turned off, the atom or molecule is assumed to have at least one bound state. We prove that, for sufficiently
small values of the fine structure constant α, the interacting system has a ground state corresponding to the bottom of its
energy spectrum. For an atom, we prove that its excited states above the ground state turn into metastable states whose life-times
we estimate. Furthermore the energy spectrum is absolutely continuous, except, perhaps,
in a small interval above the ground state energy and around the threshold energies of the atom or molecule.
Received: 3 September 1998 / Accepted: 17 March 1999 相似文献
17.
A. A. Voronkov B. P. Gorshunov V. S. Nozdrin E. S. Zhukova T. Matsuoka K. Tanaka S. Miyasaka S. Tajima M. Dressel 《JETP Letters》2012,94(9):708-713
The spectra of the conductivity and dielectric constant of La1.87Sr0.13CuO4 cuprate have been directly measured in the frequency range of 0.3 to 1.2 THz (10–40 cm−1) and the temperature range of 5 to 300 K in the E | c polarization (the electric field vector of radiation is perpendicular to the copper-oxygen planes). Excitation has been observed
in the superconducting phase, and its nature has been attributed to the transverse optical excitation of the condensate of
Cooper pairs, which appears because Josephson junctions between CuO planes are modulated due to in-plane magnetic and charge
stripes. Additional quasiparticle absorption of unknown origin has been detected at frequencies below ≈15 cm−1 at liquid helium temperatures. 相似文献
18.
E. Eriksen 《Annals of Physics》2004,313(1):147-196
We describe the electromagnetic field of a uniformly accelerated charge in its co-moving Rindler frame. It is shown that the electrical field lines coincide with the trajectories of photons. The self force of a charged particle at rest in Rindler space, and the increase of its weight due to its charge, is calculated. The general case of an accelerated charge in Rindler space is also considered. It is shown that the electrical field inside a uniformly charged spherical shell can be used as a measure of it 4-acceleration. A result that has earlier been deduced in a different way by Fugmann and Kretzschmar is confirmed, namely that the intensity of radiation from a point charge instantaneously at rest in an accelerated frame is proportional to the square of the relative acceleration of the charge and the observer. In particular it is shown that a freely falling charge in Rindler space radiates in accordance with Larmor’s formula. In this case the radiation energy is taken from the Schott energy. The energy of the electromagnetic field is analysed from the point of view of the Hirayama-separation, which generalizes the Teitelboim-separation to non-inertial frames, of the field in a bound part and an unbound part. A detailed account, with reference to the Rindler frame, of the field energy and particle energy is given for the case of a charge entering and leaving a region with hyperbolic motion. We also consider the electromagnetic field of a uniformly accelerated charge with reference to the Milne frame, which covers a different part of spacetime than the Rindler frame. The radiating part of the electromagnetic field is found in the Milne sector of spacetime. 相似文献
19.
A mathematical model of a nanoemitter for the giga- and terahertz ranges based on a carbon nanopeapod formed by a (10, 10) nanotube with encapsulated C60 fullerenes has been proposed. The fundamental possibility of the generation of giga- and terahertz radiation by a charged free fullerene oscillating in the potential well created by the atomic framework of the nanotube and several fullerenes polymerized with its walls and with each other has been proven. The radiation frequency is controlled by means of an external electric field. The dependence of the amplitude and frequency of oscillations on the charge of C60 and on the external field strength has been revealed by the molecular dynamics method. If the fullerene has a charge of +1e or +2e, it emits electromagnetic waves only in the gigahertz range in strong external fields. At the same time, the physical conditions under which the frequency of radiation can be 0.36 GHz have been established: the charge of the fullerene must be +3e, the tube should be oriented strictly along the external field lines, and the strength should be 0.1 V/nm. 相似文献
20.
E. L. Pankratov 《辐射效应与固体损伤》2013,168(9-10):844-858
ABSTRACTIn this paper, we analyzed changing of dynamics of redistribution of dopant during the manufacturing of diffusion-junction rectifier in a heterostructure due to radiation processing. In this regard, concentration of charge carriers will also be changed. We also introduce an analytical approach to analyze mass transport with account nonlinearity, space and time variation of parameters of the transport. 相似文献