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Estimation of Radio Luminosity of Pulsars and Study of Their Evolution~*

Science China Mathematics 1993年第4期36卷 468-476页

作者：吴鑫基 R.N.Manchester Department of Geophysics Peking University Beijing 100871 PRC division of radiophysics CSIRO P.O. Box 76 Epping N.S. W. 2121 Australia

The intensity distribution of emission beam and the new radio luminosity formula of pulsars are presented on the basis of the geometrical relations of polar-cap model. There are 102 pulsars with the new radio luminosity values. It is shown that the radio luminosity can be described only by one relation L∞(B/p^2)^(1.1) or L∞Q'^(-1.4) over the whole range of period and period derivatives, which is contrary to other recently suggested luminosity laws.

关键词： pulsars luminosity evolution

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Methods and Devices of Speckle-Noise Suppression (Review)

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Optics and Photonics Journal 2020年第10期10卷 219-250页

作者： Igor Kompanets Nikolay Zalyapin Quantum radiophysics division P.N. Lebedev Physical Institute Moscow Russia

Speckles in images formed by a laser beam are interference noise arising due to coherent nature of laser radiation. As the number of projection systems using laser light sources increases, new methods and devices appear for reducing the contrast of speckle-noise and thereby suppressing it. Taking into account the long-standing nature of the problem and the continuing relevance of its solution, this review discusses modern practical methods and devices—despecklers, used to reduce the speckle contrast and to achieve high quality of projected images. The review discusses the nature of the speckles appearance, considers their statistical properties, and describes the measurement of the speckle contrast. The requirements for despecklers are considered, the most important of which are speckle suppression efficiency, simplicity of design and compactness, low power consumption and low optical loss. The characteristics of different types of despecklers, including diffusers, devices based on electroactive polymers, optical waveguides, colloidal solutions and liquid crystals, as well as orthogonal phase matrices and diffraction gratings proposed as despeckers, are examined in detail. It is shown that despecklers with decorrelation of the phase front based on the mirror deformation and optical fiber have less light losses. Electro-optical-liquid crystal despecklers do not have mechanically deformable or moving elements that reduce the reliability and durability of operation, and are more compact and simple in design. A comparative table of characteristics of the most effective despecklers in which the speckle contrast is reduced to ten percent or less, with an indication of their advantages and disadvantages, is given.

关键词： Projection System Laser Beam Speckle-Noise Speckle Suppression

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四颗南天脉冲星在1560 MHz上的偏振观测

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天体物理学报 1991年第3期11卷 227-233页

作者：吴鑫基 R.N.Manchester A.G.Lyne 天文和天体物理中心CCAST(World Laboratory) division of radiophysics. CSIRO. Australia NRAL.University of Manchester. Jodrell Bank. U. K.

本文给出88年6月和7月期间在澳大利亚Parkes进行的一次南天脉冲星偏振观测的部分有意义的结果。频率为1560MHz。采用了Jodrell Bank天文台新研制成的2×16×5MHz滤波系统,使这次观测具有很强的消色散能力和较高的灵敏度。这4颗南天脉冲... 详细信息

本文给出88年6月和7月期间在澳大利亚Parkes进行的一次南天脉冲星偏振观测的部分有意义的结果。频率为1560MHz。采用了Jodrell Bank天文台新研制成的2×16×5MHz滤波系统,使这次观测具有很强的消色散能力和较高的灵敏度。这4颗南天脉冲星具有较强的线偏振,为首次获得的高频偏振资料。

关键词：脉冲星偏振观测

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ABSORPTION LINES IN THE SPECTRA OF THE QSO PKS 1448-232

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Chinese Science Bulletin 1983年第8期28卷 1075-1080页

作者：陈建生 DONALD C.MORTON BRUCE A.PETERSON ALAN E.WRIGHT DAVID L.JAUNCEY Beijing Observatory Academia Sinica Anglo-Australian Obserratory Mt. Stromlo and Siding Spring Observatory Australian National Radio Astronomical Observatory CSIRO division of radiophysics. OLD AND NEW OBSERVATIONS Savage Bolton and Wright found that the radio source PKS 1448-232 coincided with a stellar object of a magnitude about 16.4 having an ultraviolet excess. A lowresolution spectrum obtained with the Anglo-Australian 3.~m9 Telescope (AAT) confirmed this object to be a QSO with z_(em)=2.22 and revealed many absorption lines

I. OLD AND NEW OBSERVATIONS Savage, Bolton and Wright, found that the radio source PKS 1448-232 coincided with a stellar object of a magnitude about 16.4 having an ultraviolet excess. A lowresolution spectrum obtained with the Anglo-Australian 3.m9 Telescope （AAT） confirmed this object to be a QSO with zem=2.22, and revealed many absorption

关键词： Bolton Australian stellar ultraviolet Anglo Savage magnitude excess Morton inverted

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