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1.
A short review is given of results obtained at the Institute of High-Current Electronics of the Siberian Branch of the Russian
Academy of Sciences on generating high-power microwave radiation. Most of the research was devoted to a study of stimulated
Čerenkov radiation from relativistic electron beams. It is shown that the efficiency of a relativistic 3-cm backward wave
tube with a nonuniform coupling resistance can reach 35%. High-frequency radiation was discovered in the emission spectrum
of the Čerenkov oscillators and it was shown that the nature of the radiation was associated with the stimulated scattering
of low-frequency radiation by the relativistic electrons. Radiation with a power of 500 MW was obtained in the 8-mm wavelength
range using a two-beam Čerenkov oscillator. High-current pulse-periodic nanosecond accelerators with a charging device utilizing
a Tesla transformer were used in the experiments. The possibility was demonstrated of generating high-power microwave radiation
with a pulse-repetition frequency of up to 100 Hz. An average power of ∼500 W was achieved from the relativistic oscillators.
A relativistic backward wave tube with a high-current electron beam was used to make a prototype nanosecond radar device.
Some of the results presented were obtained jointly with the Russian Academy of Sciences Institute of Applied Physics. Questions
concerning multiwave Čerenkov interaction are not considered in this paper.
Institute of High-Current Electronics, Siberian Branch of the Russian Academy of Sciences, Tomsk. Translated from Izvestiya
Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 5–20, December, 1996. 相似文献
2.
We present the results of experimental and numerical studies of the phenomenon of Vavilov-Čerenkov radiation by a superluminal
radio-beam spot. We propose a technique aimed at experimental detection of normal and anomalous Doppler effects using the
VHF “Sura” facility and the UTR-3 transmitter.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 42, No. 8, pp. 740–749, August 1999. 相似文献
3.
This paper discusses the distinctive features of radiation of electromagnetic waves with anomalously large values of the wave
vector and small phase velocity that exist near narrow absorption lines. The distribution of radiated energy with respect
to angle and frequency is calculated for Čerenkov radiation and bremsstrahlung of the slow waves. It is shown that the angular
distribution of the slow-wave bremsstrahlung exhibits a characteristic maximum in the direction perpendicular to the plane
of motion of the particles.
Zh. éksp. Teor. Fiz. 112, 1557–1562 (November 1997) 相似文献
4.
M. H. Saffouri 《Il Nuovo Cimento D》1985,5(2):175-223
Summary A treatment of transition radiation between two dielectric media is presented which is based on the exact expressions for
the fields of the particle in the two media. Expressions for the spectral distribution of the energy emitted forward and for
that emitted backward are derived. The results are in accord with experimental findings for ultra-relativistic particles.
In the asymptotic region the energy spectrum becomes discrete. It is indicated how the treatment can be extended to the case
of a plate and to that of a wave guide, as well as to emission by a monopole. The case of the simultaneous emission of transition
radiation and Čerenkov radiation is considered and the relationship between them is clarified. In particular, it is shown
that, when the particle can emit Čerenkov radiation in the forward medium, it will also emit an interference signal. This
is several orders of magnitude smaller than the usual transition radiation and is concentrated in the forward direction. It
is also found that the Čerenkov wave emitted by the particle in the backward medium will be partially reflected and partially
refracted into the forward medium, after the particle crosses the boundary between the two media. The linear energy density
for the refracted wave is calculated and it is shown that under certain feasible conditions this is amenable to experimental
verification.
This work was done while the author was a summer visitor at Stanford Linear Accelerator Center, Stanford University. It was
supported by the U.S. Department of Energy, contract DE-AC03-76SF00515. 相似文献
5.
Generation of electromagnetic waves by an annular shell of plasma rotating in crossed radial electrostatic and axial magnetic
fields in a cylindrical resonator is investigated theoretically. Dispersion relations are obtained describing the interaction
of the waves with the plasma. It is shown that generation of waves by a narrow plasma shell is possible due to a cyclotron
resonance, Čerenkov resonance, or plasma resonance. Here we consider a Čerenkov resonance, where the velocities of the plasma
components and the phase velocities of the waves are perpendicular to the constant magnetic field. The frequencies and growth
rates of the waves are found under conditions of the above-mentioned resonances in a uniform and in a nonuniform plasma shell.
Advantages and disadvantages of wave generation under various conditions are noted.
Zh. Tekh. Fiz. 69, 16–21 (February 1999) 相似文献
6.
A. A. Al-rubaiee O. A. Gress K. S. Lokhtin S. I. Sinegovskii 《Russian Physics Journal》2006,49(7):727-733
The spatial distribution function of Čerenkov radiation from particles of extensive air showers with energies in the interval
1012–1017 eV calculated by the computer code CORSIKA and the approximation constructed on the basis of this calculation have allowed
us to reconstruct the events, that is, to reconstruct the type and energy of the particle that generated extensive air shower
from signal amplitudes of Čerenkov light registered with the Tunka-25 facility. The calculated spatial distribution function
of Čerenkov light is in good agreement with the fitting function constructed in [1–4] to reconstruct the parameters of extensive
air showers registered with the Tunka-25 facility.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 43–48, July, 2006. 相似文献
7.
A. I. Klimov S. D. Korovin V. V. Rostov E. M. Tot’meninov 《Radiophysics and Quantum Electronics》2006,49(10):747-753
We consider the preconditions for efficient operation of the relativistic Čerenkov microwave generator in the absence of an
external guiding magnetic field. The analytical expression for the length of propagation of a solid cylindrical electron beam
along the drift tube is obtained in the framework of the paraxial approximation. The influence of preliminary modulation of
the electron beam on the starting current of the generator and its linear efficiency is analyzed. We calculated the geometry
of a relativistic Čerenkov microwave generator with an efficiency of about 30%, in which the solid cylindrical electron beam
propagates over a short resonance decelerating system (with the length L ≈ 3λ, where λ is the radiation wavelength) in the
absence of an external magnetic field. In experiments, the efficiency of power conversion from the high-current electron beam
into the electromagnetic radiation of the E01 mode reached 8%, approximately (relative to the total current of the vacuum diode), for a power of 1.2 ± 0.3 GW and a generation
frequency of 4.06 GHz.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 10, pp. 829–836, October 2006. 相似文献
8.
B. A. P. van Rens 《Physics of Atomic Nuclei》2006,69(11):1908-1913
The ANTARES Collaboration is constructing a neutrino telescope on the bottom of the Mediterranean Sea. The main goal of ANTARES
is to detect high-energy cosmic neutrinos. The detection principle relies on the observation of Čerenkov light emitted by
neutrino-induced muons. It is shown that this type of detector is also able to detect exotic particles such as magnetic monopoles.
Above the Čerenkov limit, monopoles can be detected because of the emission of large amounts of direct Čerenkov light. Monopoles
are also detectable below the Čerenkov limit through the production of δ rays, which in turn emit Čerenkov light. The development of a software trigger for ANTARES designed for monopole detection
is presented. A simulation of the δ-ray-induced and direct Čerenkov light emission by monopoles has been made and used to study the trigger efficiency for the
detection of monopoles. Techniques to suppress background at the trigger level are presented, and plans for the future are
discussed.
for the ANTARES Collaboration
The text was submitted by the author in English. 相似文献
9.
From the aspects of classical mechanics and electrodynamics, an analysis has been performed of the possible influence of the kind of charged particle trajectory on the erenkov radiation spectrum in a crystal. Results of the analytical computation are compared with the data of a computer experiment. It is shown that the influence of the particle trajectory on the erenkov radiation spectrum is insignificant in the optical frequency band. The expected effect is possible when utilizing crystals with a superlattice and by observation of radiation in the xray frequency range.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 62–67, February, 1988.The authors are grateful to S. A. Vorob'ev for supporting the research and to Yu. L. Pivovarov for stimulating and useful discussions. 相似文献
10.
左手系材料界面上的非线性TE电磁波 总被引:4,自引:4,他引:0
针对电磁波在非线性左手系材料中的传播性质, 分别研究了左、右手系材料界面以及两左手系材料界面上非线性TE表面波的传播行为讨论了导波的频率特性、色散关系以及群速度随频率的变化规律分析表明,两种界面上的非线性TE表面波均存在频率通带和禁带,且带宽是传播功率的函数揭示了在一定条件下,左、右手系材料界面上既可以支持正向传播的非线性TE表面波,也可以支持反向传播的非线性TE表面波;两左手系材料界面上表面波的传播性质因材料参量的变化差异较大,一定参量条件下,该界面上仅支持反向传播的非线性TE表面波. 相似文献
11.
An experiment to search massive long-lived, weakly interacting particles (leptons) in cosmic radiation has been conducted
at Kolar Gold Fields at a depth of 7.6 hg cm−2 (1 hg cm−2=100 g cm−2) below surface. The apparatus was senstive to sub-relativistic (velocity<0.75 c) charged leptons of mass greater than that
of a proton and life times greater than a microsecond. The method consists of selecting charged particles using a scintillator
counter telescope and vetoing relativistic particles (velocity >0.75 c) by using a water Čerenkov detector. The range of the
particle is observed in arrays of neon flash tubes interspersed with iron absorbers. During 3000 hours of observation 28 events
were recorded satisfying the trigger and event selection criteria. Bulk of these events were interpreted as due to recoil
protons (low energy) from the inelastic scattering of high energy muons in the overhead absorber. The remaining events were
interpreted as either atmospheric stopping protons or stopping muons that failed to generate a Čerenkov signal. The observed
events are thus consistent with the background and no heavy leptons were seen. From our observations an upper limit of 2.12×10−7 (with 90% confidence level) is set on the ratio of the flux of heavy leptons to that of all muons at this depth. 相似文献
12.
A. A. Al-Rubaiee O. A. Gress K. S. Lokhtin Yu. V. Parfenov S. I. Sinegovskii 《Russian Physics Journal》2005,48(10):1004-1011
Spatial distribution of Čerenkov radiation of extensive air shower particles with energies 1013–1016 eV is simulated by the CORSIKA code for conditions and configuration of the Tunka-25 facility. Based on the calculated results,
sets of approximating functions are constructed for different primary particles and zenith angles. A comparison of the calculated
spatial distribution functions of Čerenkov light with the functions measured on the Tunka-25 facility demonstrates the feasibility
of identification of the particle initiating the shower and determination of its energy in the vicinity of the bend point
of the cosmic ray spectrum.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 7–13, October, 2005. 相似文献
13.
A. V. Razin 《Radiophysics and Quantum Electronics》2006,49(7):520-534
We study excitation of acoustic, leaky, and surface waves by a time-harmonic force source located in a homogeneous isotropic
elastic half-space contacting a homogeneous gas. The force acts in the normal direction to the interface between the media.
We consider the case where the sound velocity in the gas is less than the velocity of the Rayleigh wave propagating along
the surface of the solid. An expression is derived for the period-averaged radiation power of the surface Stoneley wave. The
total radiation power is calculated for the acoustic wave in the gas and for the leaky pseudo-Rayleigh wave. Variations in
the radiation powers of the surface and leaky waves are analyzed as functions of the source depth. If the velocities of compressional
and shear waves in the elastic medium significantly exceed the sound velocity in the gas, then the radiation power of the
Stoneley wave turns out to be a factor of 106–108 smaller than the radiation powers of other waves. The radiation power of the Stoneley wave decreases monotonically with increasing
source depth, and the decrease becomes more pronounced with the increase in the difference between the acoustic impedances
of the contacting media. If the shear-wave velocity in the solid is close to the sound velocity in the gas, then the radiation
power of the Stoneley wave is comparable with the radiation powers of other waves and exhibits maximum at a certain source
depth. For some parameters of the gas and the solid, and for certain source depths, the Stoneley wave carries away more than
a half of the total radiation power. It is shown that, for certain relations between the parameters of the media, the radiation
power of the Stoneley wave increases due to redistribution of the radiated power from the pseudo-Rayleigh leaky wave. The
total power of these waves remains approximatly constant and, with accuracy of the order of 10−3, is equal to the radiation power of the Rayleigh wave at the vacuum-solid interface. It is shown that the acoustic-wave power
which can be transmitted to the upper layers of the atmosphere during an earthquake does not exceed 0.01% of the total power
radiated at a given frequency.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 7, pp. 577–592, July 2006. 相似文献
14.
N.?N.?Rosanov 《Optics and Spectroscopy》2009,107(5):768-772
The parametric Doppler effect in a medium whose dielectric permittivity and magnetic permeability become negative in some spectral range is analyzed with respect to uniform plane waves. The regime in which the medium is right-handed (the refractive index is positive) for incident radiation and left-handed (the refractive index is negative) for reflected wave is demonstrated. The possibility of the occurrence of additional branches in the dispersion dependences is demonstrated. 相似文献
15.
Prabhakaran Letha Premlal Dinesh Chandra Tiwari Vandana Chaturvedi 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(5):78
We present a detailed theoretical analysis about the influence of surface polaritons on the transmission properties of electromagnetic waves at the periodically corrugated interface between the vacuum and left-handed material by using nonlinear boundary condition approach. The principle behind this approach is to match the wave fields across the grating interface by using a set of linear wave equation with nonlinear boundary conditions. The resonant transmission of the incident electromagnetic radiation in this structure is feasible within a certain frequency band, where there is a range of frequency over which both the electric permittivity and the magnetic permeability are simultaneously negative. The enhanced transmission is attributed to the coupling of the incident electromagnetic wave with the excited surface polaritons on grating interface. Finally, we present the numerical results illustrating the effect of the structural parameters and angle of incidence on the transmission spectra of a TM polarized electromagnetic wave. 相似文献
16.
The coexistence of TE-TM surface waves in uniaxially anisotropic left-handed materials 总被引:1,自引:0,他引:1
We investigate theoretically the characteristics of surface waves in uniaxially anisotropic left-handed materials. The constraints for the existence of TE and TM polarized surface waves in uniaxially anisotropic left-handed materials are identified. We discuss mainly whether TE and TM polarized surface modes may coexist in the same frequency domain at the interface between one isotropic regular medium and another uniaxially anisotropic left-handed medium. It is shown that the answer to the coexistence of TE and TM surface modes is really positive. The Poynting vector and the density of energy associated with surface modes are calculated. Depending on the system parameters either TE or TM surface modes has the time averaged Poynting vector directed opposite or same to the mode phase velocity. In the presence of anisotropy, negative refraction does not need to be left-handed. We show that the characteristics of surface waves in uniaxially anisotropic left-handed media are significantly different from that in isotropic left-handed media. 相似文献
17.
We report the coexistence of TE and TM surface modes in certain same
frequency domain at the interface between one isotropic regular medium and
another biaxially anistotropic left-handed medium. The conditions for the
existence of TE and TM polarized surface waves in biaxially anisotropic
left-handed materials are identified, respectively. The Poynting vector and
the energy density associated with surface modes are calculated.
Depending on the system parameters, either TE or TM surface modes can
have the
time averaged Poynting vector directed to or opposite to the mode phase
velocity. It is seen that the characteristics of surface waves in biaxially
anisotropic left-handed media are significantly different from that in
isotropic left-handed media. 相似文献
18.
J. Cirák 《Czechoslovak Journal of Physics》1965,15(4):225-235
Attention is drawn to the connection between the virtual parameters and the physical effects produced during the rapid motion of a charged particle in a mass medium. In particular, the virtual position of a particle and its virtual velocity as a function of the real velocity of the particle and the position of the observer are investigated. On the basis of such a study it was possible to formulate a new method for the interpretation of the basic properties of Vavilov-erenkov and transient radiation. This method can be used in a simple manner to determine the conditions for the occurrence and the directional characteristics of Vavilov-erenkov radiation in both a homogeneous and an inhomogeneous medium. A study of the virtual parameters of a particle on the interface between two optics of different media leads to the assumption of the existence of two kinds of transient radiation. 相似文献
19.
The propagation of electromagnetic waves in an antiferromagnetic material with the magnetoelectric effect is theoretically studied. The frequency dependences of the wavenumbers, dynamical permeability and permittivity, and reflection coefficient of electromagnetic waves for various energy parameters of the antiferromagnetic material have been obtained. It has been shown that there is a frequency range where the dynamical permeability and permittivity, as well as one of the wavenumbers, are simultaneously negative in the antiferromagnetic material with the magnetoelectric effect. In this case, the antiferromagnetic material is an example of a so-called left-handed medium. The reflection coefficient of electromagnetic waves from the surface of the antiferromagnetic material decreases anomalously in this frequency range. 相似文献
20.
M. Aglietta B. Alessandro P. Antonioli F. Arneodo L. Bergamasco C. Castagnoli A. Castellina A. Chiavassa G. Cini B. D'Ettorre Piazzoli G. Di Sciascio W. Fulgione P. Galeotti P. L. Ghia M. Iacovacci G. Mannocchi C. Morello G. Navarra L. Riccati O. Saavedra G. C. Trinchero P. Vallania S. Vernetto 《Il Nuovo Cimento C》1993,16(6):813-824
Summary The study of extensive air showers is performed at EAS-TOP by means of the combined operation of the first imaging Čerenkov
telescope and the particle e.m. array. We discuss the technical characteristics of the Čerenkov detector and its resolutions.
First data on the shape of the Čerenkov-light spots as a function of the EAS detection geometry, and on a first approach to
the study of the longitudinal development of the cascades are also presented.
Paper presented at the 6th Cosmic Physics National Conference, Palermo, 3–7 November 1992. 相似文献