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类星体3C273的近红外光变性质 被引量:3
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作者 文盛乐 彭智敏 +1 位作者 樊军辉 谢光中 《天文学报》 CSCD 北大核心 2002年第2期140-144,共5页
收集了类星体3C273的近红外资料,许由此讨论了该天体的光变性质.我们发现3C273的最大红外光变分别为△J=1.0m,△H=0.90m,△K=0.82m。
关键词 星系 类星体 3c273 基本参数 色指数 星等 近红外光谱性质
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类星体3C273的多波段光变周期分析 被引量:4
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作者 毕雄伟 和万全 +2 位作者 田家金 张青友 蔡群 《天文研究与技术》 CSCD 2012年第4期339-347,共9页
从文献中收集了类星体3C273射电、毫米、红外、光学、紫外和高能波段1963年至2006年的观测数据,获得各波段的长期光变曲线。用Jurkevich方法和离散相关函数(Discrete Correlation Function,DCF)方法分别研究了多波段的光变周期。研究结... 从文献中收集了类星体3C273射电、毫米、红外、光学、紫外和高能波段1963年至2006年的观测数据,获得各波段的长期光变曲线。用Jurkevich方法和离散相关函数(Discrete Correlation Function,DCF)方法分别研究了多波段的光变周期。研究结果表明:(1)3C273在所研究波段内的辐射流量都表现出周期性变化的特征;(2)用Jurkevich方法和离散相关函数方法分析得到的多波段变化周期的结果非常一致;(3)3C273在射电和毫米波段可能存在8.0年左右的固有周期成分,在红外、光学和紫外波段可能存在2.0年和11.0年左右的固有周期成分,在高能波段可能存在1.0年左右的固有周期成分。简要探讨了引起3C273各波段周期光变的可能原因,研究结果表明用激波加速模型(shock-in-jet)能较好地解释引起3C273多波段光变的原因。 展开更多
关键词 类星体 3c273 光变周期 JURKEVICH方法 离散相关函数
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3C273的光学光变周期 被引量:11
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作者 樊军辉 G.E.Romero 林瑞光 《天文学报》 CSCD 北大核心 2001年第1期9-15,共7页
收录了类星体 3C2 73约 1 1 0年的光学资料 ,并在此基础上讨论了光变周期性 .当用两种不同方法 (Jurkevich方法及DCF(离散相关系数 )法 )分析时 ,发现光变曲线中存在周期为 2 .0年、(1 3.65± 0 .2 0 )及 (2 2 .5± 2 .0 )年的... 收录了类星体 3C2 73约 1 1 0年的光学资料 ,并在此基础上讨论了光变周期性 .当用两种不同方法 (Jurkevich方法及DCF(离散相关系数 )法 )分析时 ,发现光变曲线中存在周期为 2 .0年、(1 3.65± 0 .2 0 )及 (2 2 .5± 2 .0 )年的周期性 . 展开更多
关键词 活动星系核 类星体3c273 光变周期性
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类星体3c273的光变周期分析 被引量:2
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作者 尹雄兵 陈洛恩 那维炜 《玉溪师范学院学报》 2007年第8期29-32,共4页
收集了类星体3c273在B波段100多年的光学资料,用结构函数对其进行了光变分析,发现3c273的光变曲线中分别存在着12.47 a、17.64 a以及22.07 a几个周期.
关键词 AGN 类星体 3c273 光变周期 结构函数
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3C273中红外-毫米波爆发的改进模型
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作者 钱善瑎 《天体物理学报》 CSCD 1999年第1期8-14,共7页
提出了一个改进的3C273中红外-毫米波爆发模型,计入在康普顿阶段和同步辐射阶段之间的过渡期间爆发源的加速,以便解释爆发上升段的细致演化,讨论了绝热阶段爆发的演化,并与14.5GHz观测作了比较.
关键词 红外-毫米波 爆发 加速模型 3c273 河外射电
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类星体3C273
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作者 Robs.,EI 肖波 《科学(中文版)》 1991年第10期7-15,共9页
关键词 类星体 3c273 频谱 结构
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离散相关函数在Blazar天体中的应用 被引量:6
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作者 王兴华 张雄 《云南师范大学学报(自然科学版)》 2010年第6期25-33,共9页
对Edelson和Krolik提出的离散相关分析方法进行了研究,用模拟信号进行了检验,结果表明这是一种比较切实可行的方法。把这种方法应用到类星体3C273的光变周期分析、各波段之间的延时分析和相关性分析中。结果表明:3C273的周期为12.88年左... 对Edelson和Krolik提出的离散相关分析方法进行了研究,用模拟信号进行了检验,结果表明这是一种比较切实可行的方法。把这种方法应用到类星体3C273的光变周期分析、各波段之间的延时分析和相关性分析中。结果表明:3C273的周期为12.88年左右,其它文献也得到了相似的结论;在延时分析中,3C273的光学波段(U波段)超前于8GHz和37GHz,22GHz超前于8GHz,37GHz超前于15GHz;3C273在红外和光学波段、光学和X射线波段、X射线和射电波段都有较好的相关性,在光学和射电波段的相关性较差。最好,我们还对DCF方法和线性回归方法进行了比较,指出了它在天文数据处理中的优势。 展开更多
关键词 DCF方法 类星体—3c273 周期 延时 相关
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利用IRAF软件进行光谱数据处理
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作者 苏云宝 王丽娜 +1 位作者 王春艳 张雄 《云南师范大学学报(自然科学版)》 2012年第1期12-15,共4页
利用专用于天文图像和数据处理的软件包IRAF,对2007年1月23日利用国家天文台2.16m望远镜获取的光谱数据进行了处理,所得到的3C273的光谱和红移值与公认值一致。
关键词 类星体 3c273 光谱数据处理 IRAF
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基于EMD-AR谱的3C 273光变周期分析
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作者 蔡剑华 刘备 +4 位作者 杨江河 庹满先 聂建军 汪胜辉 樊军辉 《天文学报》 CAS CSCD 北大核心 2022年第1期67-78,共12页
光变是Blazar最显著的观测特征之一,有的光变呈准周期性.Blazar周期光变可能为其中心黑洞和吸积盘等内部物理结构提供重要信息.因此,周期分析对于讨论Blazar的光变有重要意义.结合经验模态分解(Empirical Mode Decomposition,EMD)和自回... 光变是Blazar最显著的观测特征之一,有的光变呈准周期性.Blazar周期光变可能为其中心黑洞和吸积盘等内部物理结构提供重要信息.因此,周期分析对于讨论Blazar的光变有重要意义.结合经验模态分解(Empirical Mode Decomposition,EMD)和自回归(Auto-regressive,AR)模型谱估计方法的优点,提出了一种基于EMD-AR谱的组合光变周期分析新方法.先对观测数据进行EMD分解,得到各阶模态分量,并计算其与原始光变曲线的相关系数,再取相关度高的分量求和后估算AR谱,最后将此功率谱的周期分析方法用于天体的光变数据分析.讨论了EMD-AR谱方法的原理和应用步骤,并用此方法对类星体3C 273在1887—2016年的观测数据进行了分析,得到3C 273的长时标周期分别为:21.23、13.51、11.02、5.51、4.69、3.79、2.76 yr,与文献中常用方法的分析结果有很好的一致性;短时标周期分别为:(30±1)、(15±0.3)、(7.5±0.2)、(10±0.1)、(5±0.6)、(6±0.4)和(3±0.5)min,此结果未见相关报道,这些可能的周期相互还存在近似倍周期的关系,可为进一步的研究提供参考. 展开更多
关键词 星系:活动 星系:测光 星系:喷流 类星体:个别:3C 273
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Correlations of Active Galactic Nuclei with Microquasars
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作者 YE Yong-Chun ZUO Xue-Qin WANG Ding-Xiong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期187-192,共6页
Correlations of active galactic nuclei (AGNs) with microquasars are discussed based on the coexistence of the Blandford-Znajek (BZ) and magnetic coupling (MC) processes (CEBZMC) in black hole (BH) accretion ... Correlations of active galactic nuclei (AGNs) with microquasars are discussed based on the coexistence of the Blandford-Znajek (BZ) and magnetic coupling (MC) processes (CEBZMC) in black hole (BH) accretion disk. The proportions of several quantities of BH systems for both AGNs and microquasars are derived by combining the observational data with CEBZMC. It is shown that the square of the magnetic field at the BH horizon is inversely proportional to the BH mass, while the accretion rate of the disk is proportional to the BH mass. In addition, the very steep emissivity indexes from the recent XMM-Newton observations of the nearby bright Seyfert 1 galaxy MCG-6-30-15 and the microquasars XTE J1650-500 are well fitted by considering the MC effects on the disk radiation. These results suggest strongly the correlations of A GNs with microquasars. 展开更多
关键词 ACCRETION accretion disks MCG-6-30-15 4C+11.50 3C345 3c273 XTE J1650-500 GRO J1655-40 XTE J1550-564 GRS 1915+105
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Interpretation of the"Catastrophe"of Quasars on the Basis of New Decisions of the Problem of the Reverse Compton-Effect
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作者 Nikolay I.Perov Artem Eltsov 《Journal of Physical Science and Application》 2018年第1期55-58,共4页
In a model based on a search with increased accuracy of calculations-four times-of all the roots of the equations for the velocities of electrons in the inverse Compton effect,it is established that for new values of ... In a model based on a search with increased accuracy of calculations-four times-of all the roots of the equations for the velocities of electrons in the inverse Compton effect,it is established that for new values of the roots of the equations(corresponding to the laws of conservation of momentum and energy),the recoil electrons remain ultra-relativistic,according to the authors,allows to eliminate the reverse Compton catastrophe of quasars.The maximum value of the scattering angle of the formed particles was found to explain the thin quasar jets. 展开更多
关键词 QUASAR 3c273 critical temperature inverse COMPTON EFFECT ultra relativistic ELECTRONS limiting angle of expansion
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The Optical Variability of 3C 273
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作者 Rui-Guang Lin (Center for Astrophysics, Guangzhou University, Guangzhou 510400) E-mail: lin_rg@163.net 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第3期245-249,共5页
B-band measurements of 3C273 over some 110 years are compiled and used in a search for periodicities using the Jurkevich method. Periods of 2.0, 13.65±0.20 and 22.5±0.2yr are found. If the long-term periodic... B-band measurements of 3C273 over some 110 years are compiled and used in a search for periodicities using the Jurkevich method. Periods of 2.0, 13.65±0.20 and 22.5±0.2yr are found. If the long-term periodicity is from the instability of a slim disk, then the periodicity (~ 13yr or ~ 22-yr) suggests masses of 107M for the central black holes. 展开更多
关键词 Galaxies: active - Galaxies: individual: 3c273
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Periodic Variations of the Jet Flow Lorentz Factor in 3C 273
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作者 SHAN-JieQian Xi-ZhenZhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第3期236-244,共9页
C 273 has been observed with VLBI for more than 30 years. The entire data have shown that the position angle of the superluminal knots ejected from the core varies periodically with a period of ~15 years. Moreover, th... C 273 has been observed with VLBI for more than 30 years. The entire data have shown that the position angle of the superluminal knots ejected from the core varies periodically with a period of ~15 years. Moreover, their apparent velocity observed during the period 1963 -- 1997 has systematically decreased by a factor of 2. These remarkable properties are explained in terms of a precessing jet model, in which the ejection Lorentz factor of the superluminal knots has been decreasing during the last thirty years and has superposed on it a short-term (~5 year) oscillation. The periodic variations derived by the model-fitting are compared with the variations in the optical flux density. Binary black hole models are briefly discussed to show possible relations of the observed periods to the periods involved in a binary system (orbital motion, spin of black hole, accretion-disk rotation and Newtonian-driven precession etc.). 展开更多
关键词 Galaxies: jets - quasars: individual: 3c273 - Galaxies: nuclei - Radio Continuum: galaxies - Radiation mechanisms: nonthermal
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神秘的类星体
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作者 吴雨霖 《飞碟探索》 2010年第6期43-43,共1页
1960年,美国天文学家桑德奇用一台5米口径的光学望远镜找到了剑桥射电源第三星表上第48号天体(3C48)的光学对应体。他发现3C48的光谱中,在一个奇怪的位置上有一些又宽又亮的发射线。1963年,美国天文学家马丁·施密特发现在3C27... 1960年,美国天文学家桑德奇用一台5米口径的光学望远镜找到了剑桥射电源第三星表上第48号天体(3C48)的光学对应体。他发现3C48的光谱中,在一个奇怪的位置上有一些又宽又亮的发射线。1963年,美国天文学家马丁·施密特发现在3C273的光谱中具有与3C48类似的现象,通过仔细研究,他发现这些发射线实际上是人们早已熟知的氢的发射线,只不过朝着红光的方向移动了相当长的一段距离,也就是说它们具有非常大的红移。 展开更多
关键词 类星体 光学望远镜 天文学家 3c273 发射线 光的方向 对应体 射电源
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类星体的精准测距
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作者 方德声 《科学》 2020年第3期62-62,共1页
[本刊讯]据国家自然科学基金委员会2020年3月5日报道,在基金委多个项目的资助下,中国科学院高能物理研究所王建民团队发展了一种全新的几何方法,成功测量了类星体3C273的宇宙学距离。相关研究成果在线发表于Nature Astronomy(2020,4:517... [本刊讯]据国家自然科学基金委员会2020年3月5日报道,在基金委多个项目的资助下,中国科学院高能物理研究所王建民团队发展了一种全新的几何方法,成功测量了类星体3C273的宇宙学距离。相关研究成果在线发表于Nature Astronomy(2020,4:517)上。 展开更多
关键词 类星体 3c273 宇宙学距离 几何方法 王建民 国家自然科学基金委员会 测距 研究成果
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Optical monitoring and IDV analysis of the blazars S50716+714 and 3C 273
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作者 Xiao-Lan Liu Yu-Hai Yuan Hong-Ren Huang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第4期297-310,共14页
S50716+714 and 3C 273 are frequently studied blazars,which show obvious optical variabilities with different timescales.Using the 1.0 m telescope at the Yunnan Observatory,we monitored the two sources.For S50716+714,w... S50716+714 and 3C 273 are frequently studied blazars,which show obvious optical variabilities with different timescales.Using the 1.0 m telescope at the Yunnan Observatory,we monitored the two sources.For S50716+714,we report 990 observations during the monitoring duration from JD 2458536 to JD 2458540.For 3C 273,there are 884 observations during the monitoring duration from JD 2458539 to JD2458542.Based on those observations,we obtain the following results.(1)For S50716+714,there lie intraday optical variabilities(IDVs),with timescales from 0.31 hours to 2.64 hours.For 3C 273,it is possible that there lie IDVs,with timescales from 0.36 hours to 0.49 hours.(2)The time delay of S50716+714 isτRI=3.46 min between R and I bands,and the time delay of 3C273 isτIV=6.42 min between I and V bands.(3)We find that,for S50716+714,there lies a suspected intra-day period,P≈185.78 min;for 3C273,there lie intra-day periods,which are about~60 min and~80 min. 展开更多
关键词 quasars:general quasars:individual(S50716+714 3C 273) galaxies:photometry
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Chaotic Feature in the Light Curve of 3C 273
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作者 Lei Liu 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第6期663-668,共6页
Some nonlinear dynamical techniques, including state-space reconstruction and correlation integral, are used to analyze the light curve of 3C 273. The result is compared with a chaotic model. The similarities between ... Some nonlinear dynamical techniques, including state-space reconstruction and correlation integral, are used to analyze the light curve of 3C 273. The result is compared with a chaotic model. The similarities between them suggest there is a low-dimension chaotic attractor in the light curve of 3C 273. 展开更多
关键词 GALAXIES active - galaxies INDIVIDUAL 3C 273
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A modified stratified model for the 3C 273 jet
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作者 Wen-Po Liu Zhi-Qiang Shen 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2009年第5期520-528,共9页
We present a modified stratified jet model to interpret the observed spectral energy distributions of knots in the 3C 273 jet. Based on the hypothesis of the single index of the particle energy spectrum at injection a... We present a modified stratified jet model to interpret the observed spectral energy distributions of knots in the 3C 273 jet. Based on the hypothesis of the single index of the particle energy spectrum at injection and identical emission processes among all the knots, the observed difference of spectral shape among different 3C 273 knots can be understood as a manifestation of the deviation of the equivalent Doppler factor of stratified emission regions in an individual knot from a characteristic one. The summed spectral energy distributions of all ten knots in the 3C 273 jet can be well fitted by two components; a low-energy component (radio to optical) dominated by synchrotron radiation and a high- energy component (UV, X-ray and γ-ray) dominated by inverse Compton scattering of the cosmic microwave background. This gives a consistent spectral index of α = 0.88 (Sv ∝ v^-α) and a characteristic Doppler factor of 7.4. Assuming the average of the summed spectrum as the characteristic spectrum of each knot in the 3C 273 jet, we further get a distribution of Doppler factors. We discuss the possible implications of these results for the physical properties in the 3C 273 jet. Future GeV observations with GLAST could separate the 7-ray emission of 3C 273 from the large scale jet and the small scale jet (i.e. the core) through measuring the GeV spectrum. 展开更多
关键词 GALAXIES active -- galaxies individual (3C 273) -- galaxies jets -- radia- tion mechanisms NON-THERMAL
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Time Lags between the 22 and 37 GHz Bursts of 48 Radio-loud AGNs
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作者 Wen-Guo Deng Jin-Ming Bai +1 位作者 Li Zhang Xian Yang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第2期195-203,共9页
Based on the light curves at 22 and 37 GHz from the Metsahovi monitoring program, we investigate the time lags between the two radio bands for 48 radio-loud AGNs. DCF and ZDCF analyses are applied to the data. Our res... Based on the light curves at 22 and 37 GHz from the Metsahovi monitoring program, we investigate the time lags between the two radio bands for 48 radio-loud AGNs. DCF and ZDCF analyses are applied to the data. Our results show that there is a strong correlation between the two radio frequencies for all the sources, with the variations in the light curves at 37 GHz leading the ones at 22 GHz in general. There is no obvious differences between different sub-class AGNs as regards the time lag. In two sources, it was found that the bursts at the lower frequency lead the ones at the higher frequency. One possible explanation is that electron acceleration dominates the light curve until the radiation reaches the maximum. Some sources, such as 3C 273, 3C 279, 3C 345 and 3C 454.3, have good enough data, so we can calculate their lags burst-by-burst. Our calculations show that different outbursts have dif- ferent lags. Some bursts have positive lags, most of bursts have no clear lags, and a few have negative lags. This result means that different bursts are triggered by different mechanisms, and the interpretation for the result involves both an intrinsic and a geometric mechanism. The positive lags are well consistent with the shock model, and we use these lags to calculate the typical magnetic field strength of the radiating region. 展开更多
关键词 galaxies: active -- galaxies: individual (3C 273 3C 279 3C 345 3C 454.3) --methods: data analysis
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Spectral Reversal and Stratification of the Jet in 3C 273
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作者 Shan-JieQian Xi-ZhengZhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2001年第4期296-304,共9页
Quasi-simultaneous VLBI observations at 15-86 GHz have shown that in the classical superluminal radio source 3C273, the spectral index a (Sv ∝ vα) has a systematic variation along the jet. For epoch 1995.15, a spect... Quasi-simultaneous VLBI observations at 15-86 GHz have shown that in the classical superluminal radio source 3C273, the spectral index a (Sv ∝ vα) has a systematic variation along the jet. For epoch 1995.15, a spectral reversal was observed at core distance - 1.5 mas, where the superluminal knot C12 located. Similarly, for epoch 1997.18, two spectral reversals were observed at core distances of -1.8 mas and -4.2 mas, where superluminal knots C11 and C14 werel respectively. These spectral reversals are associated with local maxim of the jet width. We suggest that this phenomenon may be related to a stratification of the jet structure, i.e., its physical parameters (flow velocity, Doppler factor, electron density and energy, magnetic field strength, etc.) are substantially dependent on the distance from the jet axis. These properties may be naturally formed through gasdynamic processes when the jet expands into a lower pressure ambient medium. 展开更多
关键词 galaxies: active - galaxies: compact - quasars: individual: 3C 273- galaxies: jets - radio continuum: galaxies - radiation mechanisms: non-thermal
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