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91.
Xi-Liang Zhang Zhong Liu National Astronomical Observatories/ Yunnan Observatory Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Kunming China Graduate University of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2011,(10)
Mutual events between natural satellites include mutual occultation and mutual eclipse. Mutual eclipse is another kind of mutual occultation as viewed from the center of the Sun instead of the Earth. Two mutual eclipses of J2 Europa by J1 Io (2009 Aug. 28 and Sept. 12) were observed at Yunnan Observatory during the PHEMU09 international campaign. We will calculate the astrometric data of these Galilean satellites by analyzing and fitting the light curves we obtained. The limb-darkening was considered during... 相似文献
92.
Yuan Ma De-Yu Wang Jun Lin Shuo Dai Xue-Fei Zhang National Astronomical Observatories of China / Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming China Purple Mountain Observatory Nanjing China Harvard-Smithsonian Center for Astrophysics Cambridge MA USA 《中国天文和天体物理学报》2010,10(5)
We present a statistical study of decimetric type Ⅲ radio bursts,coronal mass ejections(CMEs),and Hα flares observed in the period from July 2000 to March2005.In total,we investigated 395 decimetric type Ⅲ radio burst events,21% of which showed apparent correlation to CMEs that were associated with Hα flares.We noticed that the Hα flares which were strongly associated with CMEs were gradual events,and82% of them took place before CMEs appeared in the field of view of LASCO C2;that most of the CME-associated radio bursts started in the frequency range around750 MHz with a frequency drifting rate of several hundred MHz s-1,of which both positive and negative ones were recognized; and that the correlation of type Ⅲ radio bursts to CMEs without associated flares is fairly vague,less than 9%. 相似文献
93.
Pei-Sheng Chen Xiao-Hong Yang Hong-Guang Shan National Astronomical Observatories /Yunnan Observatory Key Laboratory for the Structure Evolution of Celestial Objects Chinese Academy of Sciences Kunming China 《中国天文和天体物理学报》2010,10(4)
We collected almost all Highly Processed Data Products(HPDP)of ISO SWS01 spectra for the Galactic visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich proto-planetary nebulae(PPNs).Those infrared spectra are primarily analyzed and discussed.It is shown that either spectral shapes/peaks,or main molecular/dust features are evidenced to change in the sequence of visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich PPNs.Statistically,in this sequence,continua are gradually changed from blue to red and locations of spectral peaks of continua are also gradually changed from short wavelengths to long wavelengths.In addition,in this sequence,intensifies of main molecular/dust features are also gradually changed from prominent in the short wavelengths to prominent in the long wavelengths.Furthermore,from 2MASS and IRAS photometric data,the sequence is also proved.Results in this paper strongly support the previous suggestion for the evolution sequence of carbon-rich objects in our Galaxy,that is the sequence of visual carbon stars→infrared carbon stars→extreme carbon stars→carbon-rich PPNs. 相似文献
94.
Yan Gong Xin Wang Zheng Zheng Xue-Lei Chen National Astronomical Observatories Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China Institute for Advanced Study Einstein Drive Princeton NJ USA Center of High Energy Physics Peking University Beijing China Kavli Institute for Theoretical Physics China CAS Beijing 《中国天文和天体物理学报》2010,10(2)
The primordial non-Gaussianity (PNG) in the matter density perturbation is a very powerful probe of the physics of the very early Universe. The local PNG can induce a distinct scale-dependent bias on the large scale structure distribution of galaxies and quasars, which could be used for constraining it. We study the detection limits of PNG from the surveys of the LAMOST telescope. The cases of the main galaxy survey, the luminous red galaxy (LRG) survey, and the quasar survey of dif- ferent magnitude limits... 相似文献
95.
Rui-Zhi Yang Jin Chang Jian Wu Purple Mountain Observatory Chinese Academy of Sciences Nanjing China 《中国天文和天体物理学报》2010,10(1)
Results from PAMELA and ATIC indicate that the Kaluza-Klein type dark matter particles could be the annihilation source of the observed excess of electrons and positrons.Assuming the existence of a nearby black hole with 10000–100000 solar masses and a point source boost algorithm,we apply the standard propagation model and find that the results fit the data well. 相似文献
96.
概述了法国高层大气所空间综合孔径项目背景、科学目标以及有效载荷,介绍了该项目演示系统的基本工作原理,探讨了该演示系统的望远子系统、指向子系统、共相子系统和成像子系统,并分别给出了该演示系统在非共相控制和共相控制情况下对半导体激光器和白光点光源的成像结果,实验结果表明演示系统不同独立望远镜之间已经基本实现了共相成像。最后对该演示系统进行了总结,并指出该系统可以进一步优化之处。该演示系统对我国综合孔径成像实验研究具有一定的借鉴意义。 相似文献
97.
98.
含油气盆地碎屑岩次生优质储集层的发育,除了与广泛发育的方解石胶结相有关外,在中国西部还有一类与沸石族自生矿物胶结的成岩相有关,其中以溶蚀方沸石胶结相形成的次生优质储集层与油气聚集成藏又有十分密切的关联。经实例分析:与自生方沸石胶结有关的成岩相主要受控于扇(辫状河)三角洲前缘相带、火山岩物源和成岩早期的碱性环境;次生优质储集层的形成在时间上主要处于成岩中期A阶段,在空间上受控于邻近的烃源岩、圈闭和输导体的沟通。方沸石矿物在物理性质上具有抗压易溶(有机酸)作用,较其他常见的自生矿物(胶结物)相对优越,就方沸石易于溶蚀的特点而言是较为理想的自生矿物(胶结物)。其溶蚀对孔隙度的贡献率在50%~75%之间,发育几率占绝对优势。所以,在方沸石发育的相带中寻找以粒间溶蚀孔为主的优质储集层,具有可靠的操作性和现实性。 相似文献
99.
利用北京延庆站和海淀站风廓线产品、微波辐射计产品、北京市雷达产品(南郊和车道沟)、北京市58个称重雨量站观测资料、FY-2E卫星云图、常规气象资料综合分析2012年11月3到4日北京暴雪天气过程。分析表明:降水相态(雨、雪)由华北气旋的锋面性质和锋面位置决定;过程雨雪量由气旋的强度、持续时间和水汽通道维持时间决定;风廓线和微波辐射计产品资料在雨雪开始时间、雨雪相态转换方面有明显的指示性作用。 相似文献
100.
Zhao-Hua Xie Hong Dai Jian-Ming Hao Lei-Ming Du Xiong Zhang Physics Department Yunnan Normal University Kunming Yunnan Astrophysics Center Yunnan University Kunming Graduate School of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2007,(2)
The physics behind the spectral energy distribution (SED) of blazars remains open. We assembled 36 blazars to tackle the factors that control their SED. Now, many blazar spec- tra have the "double hump" feature in the radio and far-IR frequencies. For these a parameter, , is created to characterize the behavior of the SED. We found a significant correlation be- tween the broad-line luminosity (LBLR) and . Because LBLR is an indicator of the accreting power of the source in blazars, we derived a linear correlation, ∝ M˙1/3.18, which suggests that the SED of blazars may depend on the accretion rate, like that of BL Lac objects. We also found a significant correlation between ■ and for a sample of 11 blazars (out of one of 36) with available black hole masses. This implies the Eddington accretion ratio may influence the shape of the SED of blazars. 相似文献