检索结果-南通市图书馆

Multi-epoch X-ray observations of the narrow-line Seyfert 1 galaxy SDSS J160508.87+323921.4 with XMM-Newton

Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 207-211页

作者： AI YanLi1,2,3,YUAN WeiMin1,2,ZHOU HongYan4,5 & WANG JianGuo1,2,3 1 National Astronomical Observatories/Yunnan Observatory,Chinese Academy of Sciences,Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese Academy of Sciences,Kunming 650011,china 3 Graduate University of the Chinese Academy of Sciences,Beijing 100049,china 4 Center for Astrophysics,University of Science and Technology of china,Hefei 230026,china 5 joint institute of galaxies and cosmology,shao and ustc,shanghai 200030,china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China Graduate University of the Chinese Academy of Sciences Beijing China Center for Astrophysics University of Science and Technology of China Hefei China joint institute of galaxies and cosmology SHAO and USTC Shanghai China

We present results of multi-epoch XMM-Newton observations separated by several years of the narrow-line Seyfert 1(NLS1) galaxy,SDSS J160508.87+*** NLS1 showed X-ray flux variations on timescales of years as well as low amplitude variations on timescales as short as hours,while the X-ray spectral shape remained essentially *** spectrum shows a significant soft X-ray *** model of reflection from an ionized disc,that is dominant in the whole XMM-Newton bandpass,provides the best description of the observed spectra for all the observations,though alternatives such as Compton scattering(T-0.25 keV) cannot be ruled out in a statistical *** the disc reflection model,the observed variations may originate either from the change in the reflection fraction,or from the variability of the intrinsic X-ray luminosity.

关键词： galaxies:active Seyfert X-rays individual

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The relation between black hole masses and Lorentz factors of the jet components in blazars

引用

Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3 and Xin-Wu Cao1,2 1 shanghai Astronomical Observatory, Chinese Academy of Sciences, shanghai 200030, china 2 joint institute for Galaxy and cosmology (JOINGC) of shao and USMC, shanghai 200030, china 3 Graduate School of the Chinese Academy of Sciences, Beijing 100049, china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China joint institute for Galaxy and cosmology (JOINGC) of shao and USMC Shanghai 200030 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Long-term variation time scales in OJ 287

引用

Research in Astronomy and Astrophysics 2010年第11期10卷 1100-1108页

作者： Jun-Hui Fan Yi Liu Bo-Chun Qian Jun Tao Zhi-Qiang Shen Jiang-Shui Zhang Yong Huang Jin Wang Center for Astrophysics Guangzhou University Guangzhou 510400 China Astronomy Science and Technology Research Laboratory. of Department of Education of Guangdong Province Guangzhou 510006 China shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China joint institute for Galaxy and cosmology ShAO and USTC Chinese Academy of Sciences China

The light curve data from 1894 to 2008 are compiled for the BL Lacertae object OJ 287 from the available literature. Periodicity analysis methods （the Discrete Correlation Function-DCF, the Jurkevich method, the power spectral （Fourier） analysis, and the CLEANest method） are performed to search for possible periodicites in the light curve of OJ 287. Significance levels are given for the possible periods. The analysis results confirm the existence of the 12.2 ± 0.6 yr time scale and show a hint of a -53 yr time scale. The 12.2 ± 0.6 yr period is used as the orbital period to investigate the supermassive binary black hole system parameters.

关键词： galaxies active -- galaxies: general-- methods: data analysis -- galax- ies individual (OJ 287)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probing the Gamma-Ray Emission Region of Five TeV Flat Spectrum Radio Quasars

引用

Research in Astronomy and Astrophysics 2024年第6期24卷 156-169页

作者： Hu-Bing Xiao Hai-Tao Cao Rui Xue Jin-Ting Cai Ge-Ge Wang Marina Manganaro shao-Hua Zhang Zhi-Hao Ouyang Li-Ping Fu Jun-Hui Fan shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China School of Information Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Department of Physics Zhejiang Normal UniversityJinhua 321004China College of Mathematics and Physics Guangxi Minzu UniversityNanning 530006China Key Laboratory of cosmology and Astrophysics(Liaoning) College of SciencesNortheastern UniversityShenyang 110819China Department of Physics University of RijekaRijeka 51000Croatia Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

The location ofγ-ray emission of blazars remains a contested topic,inspiring the development of numerous investigative techniques to address this *** this work,we analyzed Fermiγ-ray light curves in the GeV and MeV bands,employing the discrete cross-correlation function method to discern time lags between the two *** 4C+21.35,Ton 599,B21420+32,and PKS 1510-089,we identified a time lag spanning several days,while for PKS 1441+25,the time lag was not statistically *** results imply that the soft photons necessary for inverse Compton scattering predominantly originate from the dusty torus in the first four sources,whereas for PKS1441+25,they seem to be sourced mainly from the broad-line *** analysis of the opacity(τγγ)and the GeV spectra study supports the conclusion that the location of the dissipation region must be beyond the BLR to avoid significant ***,for PKS 1441+25,the emission region is also posited to lie outside yet proximate to the *** parameters of describing the emission region were obtained by fitting broadband spectral energy distribution with contemporaneous observation *** findings suggest that for the five TeV FSRQs,during Te V flaring events,the jet appears to maintain an equilibrium between the energy density of the magnetic field and that of the particles for all investigated sources,with the exceptions of 4C+21.35 and PKS1441+*** terms of the overall jet power,particle energy is the dominant contributor,and the observed blazar radiation cannot be solely attributed to the magnetic field,except in the case of 4C+***,magnetic reconnection is unlikely to be the primary mechanism behind particle acceleration in these systems.

关键词： galaxies:active gamma-rays:galaxies galaxies:jets

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

脉冲星计时阵列与纳赫兹引力波探测

引用

科学通报 2024年第17期69卷 2330-2335页

作者：梁迪聪邵立晶北京大学科维理天文与天体物理研究所北京100871 中国科学院国家天文台北京100012

阿尔伯特·爱因斯坦(Albert Einstein)在1915年提出广义相对论,并在一年后就预言了引力波的存在.引力波可被看作时空的“涟漪”,几乎不与其他物质相互作用,因此能够在宇宙中自由穿梭.20世纪60年代,作为引力波探测的先行者,约瑟夫·韦伯(... 详细信息

阿尔伯特·爱因斯坦(Albert Einstein)在1915年提出广义相对论,并在一年后就预言了引力波的存在.引力波可被看作时空的“涟漪”,几乎不与其他物质相互作用,因此能够在宇宙中自由穿梭.20世纪60年代,作为引力波探测的先行者,约瑟夫·韦伯(Joseph Weber)曾宣称通过共振棒直接探测到了引力波.因为他的实验结果无法被他人重现,因而未被广泛承认.直到2015年9月14日,美国的激光干涉引力波天文台(Laser Interferometer Gravitational-Wave Observatory,LIGO)通过激光干涉的方法,首次直接探测到了引力波[1].

关键词：引力波探测脉冲星计时阵激光干涉引力波天文台广义相对论

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Clumpy Structure of Five Star-bursting Dwarf galaxies in the MaNGA Survey

引用

Research in Astronomy and Astrophysics 2024年第2期24卷 83-103页

作者： Mengting Ju Jun Yin Lei Hao Chenxu Liu Chao-Wei Tsai Junfeng Wang Zhengyi shao Shuai Feng Yu Rong Key Laboratory for Research in galaxies and cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Key Lab for Astrophysics Shanghai 200034China South-Western institute for Astronomy Research Yunnan UniversityKunming 650500China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Physics BuildingXiamen UniversityXiamenFujian 361005China College of Physics Hebei Normal UniversityShijiazhuang 050024China Hebei Key Laboratory of Photophysics Research and Application Shijiazhuang 050024China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf *** this paper,we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby galaxies at Apache Point Observatory *** the stellar population synthesis software Fitting Analysis using Differential evolution Optimization,we obtain the spatially resolved distribution of the star formation history,which allows us to construct the g-band images of the five galaxies at different *** images can help us to probe the evolution of the morphological structures of these *** images of a stellar population older than 1 Gyr are typically smooth,images of a stellar population younger than 1 Gyr reveal significant clumps,including multiple clumps which appear at different locations and even different *** study the evolutionary connections of these five galaxies to other dwarf galaxies before their star-forming clumps appear,we construct the images of the stellar populations older than three age nodes,and define them to be the images of the"host"*** find that the properties such as the central surface brightness and the effective radii of the hosts of the five galaxies are in between those of dwarf ellipticals(dEs)and dwarf irregulars(dIrrs),with two clearly more similar to dEs and one more similar to *** the five galaxies,8257-3704 is particularly interesting,as it shows a previous starburst event that is not quite visible from its gri image,but only visible from images of the stellar population at a few hundred million *** star-forming clump associated with this event may have appeared at around 600 Myr ago and disappeared at around 40 Myr ago.

关键词： galaxies dwarf-galaxies evolution-galaxies formation-Galaxy structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Bending of Jets in the QSO NRAO 530

引用

Chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 179-194页

作者： Xiao-Yu Hong Chuan-Hao Sun Jun-Hui Zhao Dong-Rong Jiang Zhi-Qiang Shen Tao An Wei-Hua Wang Jun Yang shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Graduate University of Chinese Academy of Sciences Beijing 100049 Harvard-Smithsonlan Center for Astroplaysics 60 Garden street MS 72 Cambridge MA02138 joint institute for Galaxy and cosmology

We present radio images of NRAO 530 on scales ranging from pc to kpc. The observations include the EVN at 5 GHz, the VLBA at 1.6, 8.6 and 15 GHz, the MERLIN at 1.6 and 5 GHz, and the VLA at 5, 8.4, 15, 22, and 43 GHz. The VLBI images show a core-jet structure with an oscillating trajectory on a scale of about 30 mas north of the strongest compact component （core）. Superluminal motions are detected in five of the jet components with apparent velocities in the range of 13.6 to 25.2c. A new component is detected at 15 GHz with the VLBA observations, which appears to be associated with the outburst in 2002. Significant polarized emission is detected around the core with the VLBA observations at 15 GHz. Rapid variations of the polarization intensity and angle are found between the epochs in 2002 and 2004. On the kpc-scale, a distant component （labelled as WL） located 11 arcsec west （PA=-86°） of the core is detected beyond the core-jet structure which extended to several hundreds of mas in the north-west direction （-50°）. A significant emission between the core-jet structure and the WL is revealed. A clump of diffuse emission （labelled EL, 12 arcsec long） at PA 70° to the core, is also detected in the VLA observations, suggesting the presence of double lobes in the source. The core component shows a fiat spectrum, while the distant components WL and EL have steep spectra. The steep spectra of the distant components and the detection of the arched emission suggest that the distant components are lobes or hot-spots powered by the core of NRAO 530. The morphologies from pc- to kpcscales and the bending of jets are investigated. The observed radio morphology from pc to kcp appears to favor the model in which precession or wobbling of the nuclear disk drives the helical motion of the radio plasma and produces the S-shaped structure on kpc scale.

关键词： galaxies: nuclei -- galaxies: jets -- quasars: individual: NRAO 530

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Luminosity Function of the Cluster of galaxies Abell 566

引用

Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 620-628页

作者： Quan-Bao Xiao Zheng-Yi shao Xu Zhou shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 joint institute for Galaxy ＆ cosmology Chinese Academy of Sciences Shanghai 200030 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We investigate the Luminosity Function （LF） of the cluster of galaxies Abell 566. The photometric data of 15 intermediate-bands are obtained from the Beijing-Arizona- Taiwan-Connecticut （BATC） photometric sky survey. For each of the 15 wavebands, the LF of cluster galaxies is well modelled by the Schechter function, with characteristic luminosities from -18.0 to -21.9 magnitude, from the α- to the p-band. Morphological dependence of the LF is investigated by separating the cluster members into ＇red＇ and ＇blue＇ subsamples. It is clear that late type galaxies have a steeper shape of LF than the early type galaxies. We also divided the sample galaxies by their local environment. It was found that galaxies in the sparser region have steeper shape of LF than galaxies in the denser region. Combining the results of morphological and environmental dependence of LFs, we show that Abell 566 is a well relaxed cluster with positive evidence of galaxy interaction and merger, and excess number of bright early type galaxies located in its denser region.

关键词： galaxy cluster individual Abell 566 -- galaxy photometry -- galaxy lumi- nosity function

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Inclination, Pitch Angle and Forbidden Radius of Spiral Arms of PGC 35105

引用

Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 175-180页

作者： Tao Hu Zheng-Yi shao Qiu-He Peng Department of Astronomy Nanjing University Nanjing 210093 shanghai Astronomical Observatory Chinese-Academy of Sciences Shanghai 200030 joint institute for galaxies and cosmology Chinese Academy of Sciences Shanghai 200030 joint Astrophysics Center of Chinese Academy of Sciences-Peking University Beijing 100871 The Open Laboratory of Cosmic Ray and High Energy Astrophysics Chinese Academy otSciences Beijing 100049

We have studied some properties including surface brightness in the u, g, r, i, and z bands of the nearly face-on galaxy PGC 35105. By subtracting a model surface brightness distribution from the observed image we obtain the residual image that shows only the spiral arms freed from the contamination by the bulge. From this we measured the the inclination, pitch angle, and forbidden radius （identified with the innermost point of the arm） for each of the two arms; and that for each of the five observing bands. We found these three parameters are largely independent of the observing band.

关键词： galaxies: fundamental parameters - galaxies: spiral - galaxies: structure - galaxies: surface brightness - galaxies: individual (PGC 35105)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probing the scale of new physics in the ZZγ coupling at e^+e^- colliders

引用

Chinese Physics C 2020年第6期44卷 55-86页

作者： John Ellis shao-Feng Ge Hong-Jian He Rui-Qing Xiao Department of Physics Kings College LondonStrandLondon WC2R 2LSUKTheoretical Physics DepartmentCERNCH-1211 Geneva 23SwitzerlandNICPBRävala 1010143 TallinnEstonia Tsung-Dao Lee institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China institute of Modern Physics Tsinghua UniversityBeijing 100084China Center for High Energy Physics Peking UniversityBeijing 100871China

The Z Zγtriple neutral gauge couplings are absent in the Standard Model(SM)at the tree *** receive no contributions from dimension-6 effective operators,but can arise from effective operators of *** study the scale of new physics associated with such dimension-8 operators that can be probed by measuring the reaction e^+e^-→Zγ followed by Z→■■,vv decays,at future e^+e^- colliders including the CEPC,FCC-ee,ILC and *** demonstrate how angular distributions of the final-state mono-photon and leptons can play a key rôle in suppressing SM *** further demonstrate that using electron/positron beam polarizations can significantly improve the signal *** find that the dimension-8 new physics scale can be probed up to the multiTeV region at such lepton colliders.

关键词： neutral triple gauge coupling beyond Standard Model e^+e^-colliders

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：