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Transport in Astrophysics: VI. Ultra-High Energy Cosmic Rays
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第1期65-84,共20页
Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic... Two new solutions of the homogeneous diffusion equation in 1D are derived in the presence of losses and a trigonometric profile for a profile of density. A simulation for the ankle in the energy distribution of cosmic rays (CRs) is provided in the framework of the fine tuning of the involved parameters. A theoretical image for the overall diffusion of CRs in galactic coordinates is provided. 展开更多
关键词 Cosmic rays Particle Diffusion Random Walks
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Injection Spectra of Different Species of Cosmic Rays from AMS-02, ACE-CRIS and Voyager-1
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作者 Xu Pan Qiang Yuan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期7-13,共7页
Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent ... Precise measurements of energy spectra of different cosmic ray(CR) species have been obtained in recent years, by particularly the AMS-02 experiment on the International Space Station. It has been shown that apparent differences exist in different groups of the primary CRs. However, it is not straightforward to conclude that the source spectra of different particle groups are different since they will experience different propagation processes(e.g., energy losses and fragmentations) either. In this work, we study the injection spectra of different nuclear species using the measurements from Voyager-1 outside the solar system, and ACR-CRIS and AMS-02 on the top of atmosphere, in a physical framework of CR transportation. Two types of injection spectra are assumed, the broken power-law(BPL) form and the non-parametric spline interpolation form. The non-parametric form fits the data better than the BPL form, implying that potential structures beyond the constrained spectral shape of BPL may exist. For different nuclei the injection spectra are overall similar in shape but do show some differences among each other. For the non-parametric spectral form, the helium injection spectrum is the softest at low energies and the hardest at high energies. For both spectral shapes, the low-energy injection spectrum of neon is the hardest among all these species, and the carbon and oxygen spectra have more prominent bumps in 1–10 GV in the R2 d N dRpresentation.Such differences suggest the existence of differences in the sources or acceleration processes of various nuclei of CRs. 展开更多
关键词 (ISM:)cosmic rays acceleration of particles astroparticle physics
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Refraction of extraordinary rays and ordinary rays in the Savart polariscope 被引量:3
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作者 吴俊芳 张淳民 +2 位作者 张英堂 刘汉臣 翟学军 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第7期2504-2508,共5页
The refraction of rays in the Savart polariscope is different from the isotropic medium. We have analysed and discussed the refraction of rays in the Savart polariscope on the basis of the Snell law. The refraction fo... The refraction of rays in the Savart polariscope is different from the isotropic medium. We have analysed and discussed the refraction of rays in the Savart polariscope on the basis of the Snell law. The refraction formulae of the extraordinary rays and ordinary rays were derived. Results obtained may provide theoretical and practical guide lines for studying, developing and engineering of polarization interference imaging spectrometer. 展开更多
关键词 Savart polariscope REFRACTION Snell law extraordinary rays ordinary rays
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Attenuation coefficients of gamma and X-rays passing through six materials 被引量:1
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作者 Xue-Dou Su Gao-Long Zhang +8 位作者 Shou-Ping Xu Wei-Wei Qu Lin Song Yu-Hua Huang Ben Wang Yi-Feng Wang Ze-Tao Zhang Wu-Fu Xu Ming-Li Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第1期26-31,共6页
The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chos... The aim of this study was to determine the attenuation of gamma and X-rays with different energies caused by passage through different materials.To this end,different materials with a range of atomic numbers were chosen to measure gamma and X-ray attenuation coefficients and to explore the mechanisms of interaction of gamma and X-rays with matter of various kinds.It is shown that the attenuation coefficients first decrease and then increase with increase in the radiation(photon)energy.The attenuation of gamma and X-rays passing through materials with high atomic number is greater than that in materials with low atomic number.The attenuation minimum is related to the atomic number of the irradiated materials.The larger the atomic number is,the lower the energy corresponding to attenuation minimum is.Photoelectric and Compton effects are the main processes when gamma rays pass through individual materials with high and low atomic numbers,respectively.Therefore,for radiotherapy and radiation protection,different methods should be considered and selected for the use of gamma and X-rays of different energies for use in different materials. 展开更多
关键词 Attenuation coefficient Interaction mechanisms Gamma rays High-energy X-rays Therapy and protection
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面向媒体融合的出版企业内容运营策略——以RAYS平台为例 被引量:6
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作者 白立华 刘永坚 施其明 《传媒》 CSSCI 北大核心 2018年第2期68-70,共3页
在媒体融合中,优质内容资源的合理运营是传统出版企业实现转型升级的基础。但当前许多传统出版企业尚未找到合适的内容运营策略,出版融合之路步履维艰。本文就我国传统出版企业内容运营现状进行分析,阐述了媒体融合中"内容为王&qu... 在媒体融合中,优质内容资源的合理运营是传统出版企业实现转型升级的基础。但当前许多传统出版企业尚未找到合适的内容运营策略,出版融合之路步履维艰。本文就我国传统出版企业内容运营现状进行分析,阐述了媒体融合中"内容为王"策略的重要性,结合武汉理工数字传播工程有限公司RAYS平台的探索与实践,从生产与消费互动的独特运营模式、出版行业大数据服务、多元化的盈利模式和内容运营人才培养方面分析其帮助传统出版企业展开内容运营的策略,以期为我国传统出版企业的内容运营提供参考。 展开更多
关键词 出版企业 媒体融合 内容运营 rays平台
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The characteristics of DNA repair synthesis induced by DNA polymerase β in hepatoma cells after γ rays irradiation 被引量:2
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作者 CAI Jian_Ming 1, ZHENG Xiu_Long 1, LUO Cheng_Ji 2, GAO Jian_Guo 1 and CHENG Tian_Min 2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1997年第2期18-20,共3页
ThecharacteristicsofDNArepairsynthesisinducedbyDNApolymeraseβinhepatomacelsafterγraysiradiationCAIJian_Ming... ThecharacteristicsofDNArepairsynthesisinducedbyDNApolymeraseβinhepatomacelsafterγraysiradiationCAIJian_Ming1,ZHENGXiu_Long1,... 展开更多
关键词 DNA POLYMERASES DNA REPAIR γ rays LIVER neoplasmas liver/radiation effects
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An algorithm to resolve γ-rays from charged cosmic rays with DAMPE 被引量:2
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作者 Zun-Lei Xu Kai-Kai Duan +18 位作者 Zhao-Qiang Shen Shi-Jun Lei Tie-Kuang Dong Fabio Gargano Simone Garrappa Dong-Ya Guo Wei Jiang Xiang Li Yun-Feng Liang Mario Nicola Mazziotta Maria Fernanda Munoz Salinas Meng Su Valerio Vagelli Qiang Yuan Chuan Yue Jing-Jing Zang Ya-Peng Zhang Yun-Long Zhang Stephan Zimmer 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第3期25-36,共12页
The DArk Matter Particle Explorer(DAMPE),also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne observatory.One of the main scientific goals o... The DArk Matter Particle Explorer(DAMPE),also known as Wukong in China,which was launched on 2015 December 17,is a new high energy cosmic ray and γ-ray satellite-borne observatory.One of the main scientific goals of DAMPE is to observe Ge V-Te V high energy γ-rays with accurate energy,angular and time resolution,to indirectly search for dark matter particles and for the study of high energy astrophysics. Due to the comparatively higher fluxes of charged cosmic rays with respect to γ-rays,it is challenging to identify γ-rays with sufficiently high efficiency,minimizing the amount of charged cosmic ray contamination. In this work we present a method to identify γ-rays in DAMPE data based on Monte Carlo simulations,using the powerful electromagnetic/hadronic shower discrimination provided by the calorimeter and the veto detection of charged particles provided by the plastic scintillation detector. Monte Carlo simulations show that after this selection the number of electrons and protons that contaminate the selected γ-ray events at~10 Ge V amounts to less than 1% of the selected sample.Finally,we use flight data to verify the effectiveness of the method by highlighting known γ-ray sources in the sky and by reconstructing preliminary light curves of the Geminga pulsar. 展开更多
关键词 gamma rays general - instrumentation detectors - methods data analysis
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EXCESS FUNCTIONS OF RAYS ON COMPLETE NONCOMPACT MANIFOLDS 被引量:1
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作者 徐森林 徐栩 《Acta Mathematica Scientia》 SCIE CSCD 2003年第3期339-344,共6页
This paper gives an estimate of excess functions of rays on complete non-compact manifolds. By using this estimation, the authors can get the results in [3] as corollaries, which asserts that a complete manifold is di... This paper gives an estimate of excess functions of rays on complete non-compact manifolds. By using this estimation, the authors can get the results in [3] as corollaries, which asserts that a complete manifold is diffeomorphic to Rn under some curvature and pinching conditions. At last, they obtain a refinement of them with extra Ricci condition. 展开更多
关键词 Excess functions rays DIFFEOMORPHISM
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The Anisotropy of Cosmic Rays and the Global Anisotropy of Physical Space 被引量:1
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作者 Yuriy Alexeevich Baurov 《Journal of Modern Physics》 2012年第11期1744-1748,共5页
The influence of a new anisotropic factor onto the mechanism of accelerating cosmic rays up to ultrahigh energies (CR UHE) due to a new global natural force with the anisotropic behavior is considered. The directions ... The influence of a new anisotropic factor onto the mechanism of accelerating cosmic rays up to ultrahigh energies (CR UHE) due to a new global natural force with the anisotropic behavior is considered. The directions in the physical space along which CR UHE can arrive, are predicted. A brief comparative analysis of these directions together with the obtained experimental results is given. Their qualitative coincidences are shown. 展开更多
关键词 ANISOTROPY of COSMIC rays GLOBAL ANISOTROPY New FORCE
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基于RAYS的技术创新模式及对出版融合的影响 被引量:3
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作者 刘永坚 白立华 +1 位作者 施其明 郭雪吟 《中国传媒科技》 2019年第6期19-21,共3页
对于出版业来说,供需不匹配、产能过剩、读者流失等问题长期存在。在当前媒介融合发展的大背景下,传统的出版模式已经不足以满足出版业提升市场竞争力的迫切需求。本文首先分析了出版行业融合发展面临的现状与存在的问题;接着分析了RAY... 对于出版业来说,供需不匹配、产能过剩、读者流失等问题长期存在。在当前媒介融合发展的大背景下,传统的出版模式已经不足以满足出版业提升市场竞争力的迫切需求。本文首先分析了出版行业融合发展面临的现状与存在的问题;接着分析了RAYS系统的技术模式及其关键技术的功能,并阐述了其对出版融合所产生的积极影响。全文深入地解析了RAYS系统如何推动传统出版业在内容、渠道、平台、经营、管理等方面的深度融合,如何构建了新的互联网知识服务生态。 展开更多
关键词 rays 出版融合 技术创新 大数据 云计算
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“互联网+”背景下的外语教育出版思考——以RAYS平台为例 被引量:1
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作者 陈妍宏 《科技传播》 2020年第1期172-173,共2页
"互联网+"背景下,外语教育出版在生存发展和更好为外语教育服务的双重压力下面临转型。转型过程中需解决传统出版与数字出版的关系问题,以及协调出版单位、作者、读者、编辑四者之间的关系。文章以RAYS平台为例,通过对该转型... "互联网+"背景下,外语教育出版在生存发展和更好为外语教育服务的双重压力下面临转型。转型过程中需解决传统出版与数字出版的关系问题,以及协调出版单位、作者、读者、编辑四者之间的关系。文章以RAYS平台为例,通过对该转型模式的分析,探寻当代外语教育出版如何应对挑战,如何抓住发展机遇,为我国的外语教育事业贡献绵薄之力。 展开更多
关键词 “互联网+” 外语教育出版 rays平台
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The Accurate Mass Formulas of Leptons, Quarks, Gauge Bosons, the Higgs Boson, and Cosmic Rays 被引量:2
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2016年第12期1591-1606,共16页
One of the biggest unsolved problems in physics is the particle masses of all elementary particles which cannot be calculated accurately and predicted theoretically. In this paper, the unsolved problem of the particle... One of the biggest unsolved problems in physics is the particle masses of all elementary particles which cannot be calculated accurately and predicted theoretically. In this paper, the unsolved problem of the particle masses is solved by the accurate mass formulas which calculate accurately and predict theoretically the particle masses of all leptons, quarks, gauge bosons, the Higgs boson, and cosmic rays (the knees-ankles-toe) by using only five known constants: the number (seven) of the extra spatial dimensions in the eleven-dimensional membrane, the mass of electron, the masses of Z and W bosons, and the fine structure constant. The calculated masses are in excellent agreements with the observed masses. For examples, the calculated masses of muon, top quark, pion, neutron, and the Higgs boson are 105.55 MeV, 175.4 GeV, 139.54 MeV, 939.43 MeV, and 126 GeV, respectively, in excellent agreements with the observed 105.65 MeV, 173.3 GeV, 139.57 MeV, 939.27 MeV, and 126 GeV, respectively. The mass formulas also calculate accurately the masses of the new particle at 750 GeV from the LHC and the new light boson at 17 MeV. The theoretical base of the accurate mass formulas is the periodic table of elementary particles. As the periodic table of elements is derived from atomic orbitals, the periodic table of elementary particles is derived from the seven principal mass dimensional orbitals and seven auxiliary mass dimensional orbitals. All elementary particles including leptons, quarks, gauge bosons, the Higgs boson, and cosmic rays can be placed in the periodic table of elementary particles. The periodic table of elementary particles is based on the theory of everything as the computer simulation model of physical reality consisting of the mathematical computation, digital representation and selective retention components. The computer simulation model of physical reality provides the seven principal mass dimensional orbitals and seven auxiliary mass dimensional orbitals for the periodic table of elementary particles. 展开更多
关键词 Mass Formulas Particle Masses LEPTONS QUARKS Gauge Bosons Higgs Boson Cosmic rays The Periodic Table of Elementary Particles Computer Simulation Knees-Ankles-Toe The Theory of Everything
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KELEA, Cosmic Rays, Cloud Formation and Electromagnetic Radiation: Electropollution as a Possible Explanation for Climate Change 被引量:1
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作者 W. John Martin 《Atmospheric and Climate Sciences》 2016年第2期174-179,共6页
The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attr... The basic premise of this article is that human generated electromagnetic radiation is contributing to global warming. It may do so by diverting an energy force termed KELEA (kinetic energy limiting electrostatic attraction) from its presumed association with cosmic rays. Cosmic ray delivered KELEA is viewed as normally participating in the formation of cloud condensation nuclei (CCN). It may do so by transforming electrostatically inert particles into electrostatic aerosols capable of acting as CCN. The resulting clouds act as a reflective barrier to some of the infrared radiation from the sun and, thereby, reduce the earth’s heat. This article proposes that increasing levels of electromagnetic radiation in the atmosphere is reducing the capacity of cosmic rays to deliver adequate KELEA to maintain climate stability through optimal cloud formation. Specifically, the fluctuating electrical fields accompanying electromagnetic radiation may do so by competitively withdrawing some of the KELEA from the incoming cosmic rays. Previously described studies by Dr. Wilhelm Reich attributed to an energy force termed orgone, are consistent with weather activity being inducible using a device that likely delivers KELEA to the atmosphere. In addition to the foregoing consideration, there are many agricultural and industrial applications of KELEA activated fluids that can reduce carbon emissions. It is important that the scope of climate science be broadened to include a detailed understanding of KELEA and of its many potential practical applications in addressing global warming. 展开更多
关键词 Climate Change CLOUD Cosmic rays Electromagnetic Radiation KELEA Orgone WATER Cell Phone
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Analyzing the transient effects of 60Co gamma rays in a CIS by Monte Carlo method
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作者 Yuan-Yuan Xue Zu-Jun Wang +8 位作者 Min-Bo Liu Rui Xu Hao Ning Wen Zhao Bao-Ping He Zhi-Bin Yao Jiang-Kun Sheng Wu-Ying Ma Guan-Tao Dong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期100-106,共7页
The objective of this work is to analyze the transient effects of ^60Co gamma rays in the CMOS image sensor (CIS) using the Monte Carlo method, based on Geant4. The track, energy spectrum, and angle of produced electr... The objective of this work is to analyze the transient effects of ^60Co gamma rays in the CMOS image sensor (CIS) using the Monte Carlo method, based on Geant4. The track, energy spectrum, and angle of produced electrons when gamma rays traversed a silicon or silicon dioxide cube were calculated. A simplified model of a 500 × 500 CIS array was established, and the transient effects of gamma rays in the CIS were simulated. The raw images were captured when the CIS was irradiated by gamma rays. The experimental results were compared with the simulation results. The characteristics of the typical events induced by transient effects were analyzed. 展开更多
关键词 ^60CO GAMMA rays Transient effects CMOS image sensor (CIS) GEANT4
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Bending-Rays Imaging Based on Genetic Algorithm
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作者 Foundation item: Liu Huai lin, Liu Hong, Chen Shu zhen College of Electronic Information, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期585-588,共4页
Basic principle of bending rays imaging is discussed briefly and an improved genetic algorithm is presented to settle the converse computation of bending rays imaging. Compared with other algorithms, this one improv... Basic principle of bending rays imaging is discussed briefly and an improved genetic algorithm is presented to settle the converse computation of bending rays imaging. Compared with other algorithms, this one improves the velocity, quality and stability of imaging efficiently. Experiment results are provided in the end. 展开更多
关键词 genetic algorithm bending rays incomplete projection travel time
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THE RELATIONSHIP BETWEEN RADIATION DOSE AND CHROMOSOME ABERRATIONS AND MICRONUCLEI IN RABBITS EXPOSED TO FRACTIONATED WHOLE-BODY ^(60)Co GAMMA RAYS
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《癌变.畸变.突变》 CAS CSCD 1991年第S1期4-4,共1页
The frequencies of chromosome aberrationsand micronuclei showed an increase withdoses after irradiation of rabbitsexposed to fractionated or single whole-body <sup>60</sup>Co gamma rays.At most dose points,
关键词 fractionated GAMMA CHROMOSOME irradiation CO GAMMA rays GAMMA ABERRATION body quadratic doses
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新技术引领的出版融合模式创新——以RAYS系统为例 被引量:1
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作者 刘永坚 白立华 +1 位作者 施其明 郭雪吟 《中国传媒科技》 2020年第3期36-37,共2页
科技是出版的本质属性之一,新技术的发展对推动出版业的进步具有重要影响。在新的数字技术驱动下,出版业正在进行新一轮的技术融合与变革。本文首先分析了当前出版融合技术发展的背景,分别从国家战略、技术环境、产业态势入手分析了现... 科技是出版的本质属性之一,新技术的发展对推动出版业的进步具有重要影响。在新的数字技术驱动下,出版业正在进行新一轮的技术融合与变革。本文首先分析了当前出版融合技术发展的背景,分别从国家战略、技术环境、产业态势入手分析了现阶段出版与技术融合发展的良好环境;接着,以RAYS系统为例,从社群运营服务、大数据、内容精准投送及多角色的知识技术服务链四个方面深入分析了其技术创新模式及对出版融合的影响;最后,具体阐述了RAYS的技术创新模式对未来出版融合产生的影响。本文通过对以RAYS系统为代表的新技术引领下出版融合模式创新的分析,深度阐释了科技对出版融合的关键作用。 展开更多
关键词 rays 出版融合
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Study of a solar flare on 2005 August 22 observed in hard X-rays and microwaves
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作者 Zhong-Yin Liu You-Ping Li +1 位作者 Wei-Qun Gan Kazi A.Firoz 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第1期64-76,共13页
We investigate the 2005 August 22 flare event(00:54 UT) exploiting hard X-ray(HXR) observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager(RHESSI) and microwave(MW) observations from the No... We investigate the 2005 August 22 flare event(00:54 UT) exploiting hard X-ray(HXR) observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager(RHESSI) and microwave(MW) observations from the Nobeyama Solar Radio Observatory. The HXR time profile exposes well-damped quasi-periodic pulsations with four sequential peaks, and the MW time profile follows the corresponding peaks.Based on this feature, we derive the time relationship of HXRs and MWs with multifrequency data from the Nobeyama Radio Polarimeter, and the spatially resolvable data from RHESSI and the Nobeyama Radioheliograph. We find that both frequency dependent delays in MWs and energy dependent delays in HXRs are significant.Furthermore, MW emissions from the south source are delayed with respect to those from the north source at both 17 GHz and 34 GHz, but no significant delays are found in HXR emissions from the different sources at the same energies. To better understand all these long time delays, we derive the electron fluxes of different energies by fitting the observed HXR spectra with a single power-law thick-target model, and speculate that these delays might be related to an extended acceleration process. We further compare the time profile of a MW spectral index derived from 17 and 34 GHz fluxes with the flux densities, and find that the spectral index shows a strong anticorrelation with the HXR fluxes. 展开更多
关键词 Sun: flares Sun: radio radiation Sun: X-rays gamma rays
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Scattering from Rough Surfaces Using the"Shooting and Bouncing Rays" Technique
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作者 Gao Huo-tao Ke Heng-yu +1 位作者 Hou Jie-chang Wu Shi-cai 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第3期319-321,共3页
The “shooting and bouncing rays” (SBR) technique is used to analyze the electromagnetic scattering characters of ocean rough surfaces varying with time. Some numerical results are presented and compared with the met... The “shooting and bouncing rays” (SBR) technique is used to analyze the electromagnetic scattering characters of ocean rough surfaces varying with time. Some numerical results are presented and compared with the method of moments, and some factors, such as the incident angle, polarization and frequency are investigated which influence on electromagnetic scattering characters of ocean rough surfaces. 展开更多
关键词 “shooting and bouncing rays technique electromagnetic scattering characters ocean rough surfaces
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Rays’ Change of Directions between Inertial Frames and Stellar Aberration
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作者 Caesar P. Viazminsky Piere K. Vizminiska 《Applied Mathematics》 2015年第9期1553-1562,共10页
The path of a light’s signal is one and the same in the universal space regardless of the inertial frame by which it is identified. However, only one frame can be taken stationary and identified with the universal sp... The path of a light’s signal is one and the same in the universal space regardless of the inertial frame by which it is identified. However, only one frame can be taken stationary and identified with the universal space while all other frames are moving. The direction of the path of a light’s pulse in a moving frame is determined in terms of its direction in the stationary one;the result is utilized to explain stellar aberration and show that the tilted direction in the moving frame depends only on its velocity. The aberration increment vector is introduced and employed to determine the apparent position of a star at each point of the earth orbit. Aberration in an earth satellite relative to the geocentric frame is presented. The direction’s change of a light beam between graded inertial frames promotes explaining aberration in an earth’s satellite in parallel to stellar aberration on earth. 展开更多
关键词 Direction’s CHANGE of Light rays STELLAR ABERRATION ABERRATION in a Satellite ABERRATION INCREMENT Graded Inertial Frames
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