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1.
We calculate the Stokes parameters of synchrotron radiation of the interstellar medium for the model of radiation source consisting of N homogeneous layers. The calculations take into account the variance of the Faraday rotation. The results of polarization measurements of the North Spur and a region of strong linear polarization of radio emission with coordinates 1950=4 h 30 m and 1950=61°, performed at the Radiophysical Research Institute (NIRFI) at 25 frequencies in the interval 195-1250 MHz, are presented. Based on the models considered, we discuss the spectra of polarization temperature of these regions.  相似文献   

2.
对金属表面热红外偏振特性的模型进行了研究,在建模中不仅考虑了金属表面的统计特性,也考虑了特别粗糙的金属表面存在的遮蔽效应问题.通过计算机模拟出不同表面粗糙度的金属板热红外偏振度和金属表面热红外辐射角之间的关系曲线,并和实验获得的结果进行了对比.对于表面粗糙度为1.6um的较为光滑的金属表面,模拟的结果基本吻合了实验中获得的数据.对于表面粗糙度为6.8um的较为粗糙的金属表面,仿真出的结果和实验中获得的数据相差较大.但在考虑了遮蔽效应后,模型模拟的结果得到了很大的改善.通过对模型的研究.分析确定了对金属板表面热红外偏振度影响的主要因素.  相似文献   

3.
Polarized |S|=0.99±0.01 $| S | = 0.99 \pm 0.01$, and unpolarized |S|=0.03±0.01 $| S | = 0.03 \pm 0.01$ emission from a single emitter embedded in a single, cylindrically symmetric device design is presented. The polarization stems from a position offset of the single emitter with respect to the cavity center, which breaks the cylindrical symmetry, and a position-dependent coupling to the frequency degenerate eigenmodes of the resonator structure is shown. The experimental results are interpreted by using numerical simulations and by experimental mapping of the polarization-resolved far-field emission patterns. The findings can be generalized to any nanophotonic structure where two orthogonal eigenmodes are not fully spatially overlapping.  相似文献   

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A special system created to register short electromagnetic pulses has been used to study high-frequency (0.1–30 MHz) radio emission of lightning discharges. It has been shown that the emission is a sequence of short pulses. The shape, width, and amplitude of the first (bipolar) pulse agree with those predicted by theory with account for the combined action of the effect of the runaway electron breakdown and an extensive atmospheric shower for the energy of the initial particle of the order of 1016 eV. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 9, pp. 800–809, September 2005.  相似文献   

6.
We propose an interpretation of some observations of the ordinary (o) mode in the microwave emission of slowly-varying (s) radio sources associated with active regions in the solar atmosphere. As a rule, the extraordinary (e) mode dominates in the s-component, which is fully explained by the generally accepted theory of its origin. This theory is based on the cyclotron and bremsstrahlung mechanisms of radiation of thermal electrons in an inhomogeneous plasma of the solar atmosphere above sunspots, where the magnetic field decreases and the kinetic temperature increases with height. It is shown in this work that the prevalence of the ordinary mode is due most probably to the presence of a region with a negative gradient of the kinetic temperature in the atmosphere above the sunspot. We analyze the qualitative frequency dependences of the brightness temperature and polarization of the radiation of a hot and cold (compared to the ambient plasma) filament in the s-component source, as well as the possible reasons for the polarization reversal at a certain frequency. Special attention is paid to the active region NOAA 4741 with the unipolar sunspot described in [1, 2]. Criteria permitting one to judge which of two effects (linear wave coupling or presence of a region with a negative temperature gradient) is responsible for the o-mode in the s-component are discussed.  相似文献   

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金属表面粗糙度对热红外偏振特性影响研究   总被引:3,自引:2,他引:3  
汪震  洪津  叶松  张冬英  王峰 《光子学报》2007,36(8):1500-1503
根据热红外偏振的原理和探测方法,利用一种热红外偏振探测系统分别研究了铝质和钢质金属板热红外偏振度和其表面粗糙度之间的关系.金属板的表面粗糙度通过喷砂和刨床加工控制.实验结果分析表明:在观测角较小时,喷砂方式处理的金属目标板,粗糙度对它们的热红外偏振度影响较小;而刨床加工的金属目标板,粗糙度对它们的热红外偏振度影响较大.在观测角较大时,无论经过何种加工方式处理表面的金属目标板,都遵循表面越是光滑其热红外偏振度越大的规律.  相似文献   

9.
刘美荣 《光谱实验室》2012,29(2):698-701
电磁波检测技术的应用,可以防止对人体的辐射。当今无线通讯技术迅猛发展,如何对变电所及输电线与移动电话基地台所产生的电磁场强度进行评估,便成为一个重要的工作。通过分析电磁波特征,提出了对这些电磁波辐射设施所产生的电磁场强度检测的方法。  相似文献   

10.
Radiophysics and Quantum Electronics - We report on the results of studying the radio emission of the Rydberg states of atoms and molecules in the Earth’s upper atmosphere at ionospheric...  相似文献   

11.
The spontaneous emission (SE) progress of polarized atoms in a stratified structure of air-dielectric(DO)-metal(M) dielectric(D1)-air can be controlled effectively by changing the thickness of the D1 layer and rotating the polarized direction of atoms. It is found that the normalized SE rate of atoms located inside the DO layer crucially depends on the atomic position and the thickness of the D1 layer. When the atom is located near the DO-M interface, the normalized atomic SE rate as a function of the atomic position is abruptly onset for the thin D1 layer. However, with the increasing thickness of the D1 layer, the corresponding curve profile exhibits plateau and stays nearly unchanged. The substantial change of the SE rate stems from the excitation of the surface plasmon polaritons in metal-dielectric interface, and the feature crucially depends on the thickness of D1 layer. If atoms are positioned near the DO-air interface, the substantial variation of the normalized SE rate appears when rotating the polarized direction of atoms. These findings manifest that the atomic SE processes can be flexibly controlled by altering the thickness of the dielectric layer D1 or rotating the orientation of the polarization of atoms.  相似文献   

12.
Russian Physics Journal - Based on the use of the vector apparatus and the Jones matrices, a polarization-modulation method for bearing of a moving object from radio beacon signals orthogonally...  相似文献   

13.
Manipulation of spontaneous emission from an atom confined in three kinds of modified reservoirs has been investigated by means of an elliptically polarized laser field. Some interesting phenomena such as the multi-peak structure, extreme spectral narrowing, and cancellation of spontaneous emission can be observed by adjusting controllable system parameters. Moreover, these phenomena depend on the constructive or destructive quantum interference between multiple decay channels and which can be changed appreciably by varying the phase difference between the two circularly polarized components of the probe field. These results demonstrate the importance of an elliptically polarized laser field in controlling the spontaneous emission and its potential applications in high-precision spectroscopy.  相似文献   

14.
Using the photon closed orbit theory, the spontaneous emission rate of a polarized atom in a medium between two parallel mirrors is derived and calculated. It is found that the spontaneous emission rate of a polarized atom between the mirrors is related to the atomic position and the polarization direction. The results show that in the vicinity of the mirror, the variation of the spontaneous emission rate depends crucially on the atomic polarization direction. With the increase of the polarization angle, the oscillation in the spontaneous emission rate becomes decreased. For the polarization direction parallel to the mirror plane, the oscillation is the greatest; while for the perpendicular polarization direction, the oscillation is nearly vanished. The agreement between our result and the quantum electrodynamics result suggests the correctness of our calculation. This study further verifies that the atomic spontaneous emission process can be effectively controlled by changing the polarization orientation of the atom.  相似文献   

15.
Polarized Emission of an Eu^3+ Doped Azo-Polymer Waveguide   总被引:1,自引:0,他引:1       下载免费PDF全文
We investigate the polarized emission behaviour of an Eu^3 doped azo-polymer waveguide. Affected by the azobenzene groups in the photoinduced orientation process by the 532nm linearly polarized laser, the ligands were realigned orderly perpendicular to the direction of the orientation direction. This leads to the polarized absorption and emission of the waveguide in the orientation direction. By an m-line apparatus based on the prism coupling technique, two guided propagation modes were observed in the waveguide, and the refractive index at 650hm in TE polarizations is 1. 7505.  相似文献   

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Radiophysics and Quantum Electronics - On the basis of using the Jones vectors and matrices, we develop the polarization-modulation method for determining the aircraft bearing and roll by the...  相似文献   

18.
We present the results of theoretical studies of the structure of thermal radio emission from the Earth's atmosphere in the middle part of the submillimeter wavelength range (wave numbers 1/ 20–50 cm-1). Absorption spectra of the atmosphere, heights at which the radiation is formed, and other physical factors, which determine the features of the inverse problems of remote sensing in the band considered, are analyzed.  相似文献   

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20.
Different methods for the interpretation of linear dichroic spectra of molecules incorporated in uniaxial matrices are discussed. A method based on the combination of both polarized absorption and emission measurements is described for the resolution of absorption and emission spectra into their different polarized components, and for the investigation of molecular distributions in the oriented matrix. The distributions of some planar molecules of different shapes incorporated in stretched polyethylene films are presented.  相似文献   

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