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题名	射电噪窄线赛弗特 1型活动星系核的光学微光变监测
作者	时光
学位类别	硕士
答辩日期	2011-05-26
授予单位	中国科学院研究生院（云南天文台）
授予地点	北京
导师	袁为民 ; 单红光
关键词	活动星系核 赛弗特星系 类星体 测光 喷流
其他题名	optical microvariability monitoring of Radio-loud Narrow-line Seyfert 1 Active Galactic Nuclei
学位专业	天体物理
中文摘要	射电噪窄线赛弗特 1活动星系核（简称：射电噪窄线Seyfert 1），是活动星系核中非常稀少的一个子类，仅占窄线赛弗特 1星系的 7%。Yuan et al.（2008）指出射电噪窄线Seyfert 1显示出类似blazar的宽波段特性。观测上的证据包括：致密的VLBI核区、很高的射电亮温度、平射电谱和射电波段的快速光变、X-射线谱以及类似blazar的宽波段能谱分布。一般认为，活动星系核中的gamma-射线辐射是来自相对论性喷流中的逆康普顿散射，Fermi LAT探测到这类天体的高能gamma-射线辐射，证实了射电噪窄线Seyfert 1存在相对论性喷流。在blazar中通常能观测到光学波段的微光变（optical microvariability），它被认为是喷流中聚束效应的典型特征，所以我们预期射电噪窄线Seyfert 1（至少其中的一部分）也应该存在光学波段的微光变。本文详细介绍了我们对一个射电噪窄线Seyfert 1活动星系核小样本的光学观测工作。我们利用云南天文台丽江2.4m望远镜对样本中的五个成员进行光学波段的监测，目的是探测射电噪窄线Seyfert 1活动星系核的光学微光变。 第二章我们主要总结射电噪窄线Seyfert 1活动星系核在各个电磁波段的观测特征（类似blazar的特性），以及这类活动星系核物理机制和驱动的可能理论解释。第三章我们应用Yuan et al.（2008）的选源标准，根据光学光谱数据和射电观测数据，组建了一个小的射电噪窄线Seyfert 1样本。这个样本由五个典型的射电噪窄线Seyfert 1组成，同时我们还介绍了样本中个源在以往的研究中的观测特征。 第四章我们主要介绍射电噪窄线Seyfert 1样本的观测结果。我们利用2.4m光学望远镜在7个观测夜对样本成员进行R和V波段的交替观测，并在文章中给出了光学微光变的观测结果和光变检验结果。我们探测到了样本中5个射电噪窄线Seyfert 1存在较大幅度而且快速的光变，光变时标仅为小时到天的量级。在R和V两个光学波段，2MASX J0324+3410、SDSS J1254+1141和SDSS J0849+5108的典型光变幅度分别接近0.1mag、0.06mag和0.25mag。对于另外两个源SDSS J0814+5609和SDSS1505+0326，我们也获得了初步的观测结果，存在明显的光学微光变，变幅均 > 0.1mag。我们的观测结果表明，这类天体的光学辐射，至少有一部分是来自喷流的非热辐射的贡献，同时也支持了以往射电噪窄线Seyfert 1的多波段观测结果和最近GLAST Fermi卫星的高能gamma-射线的探测结果。 第五章介绍我们对丽江2.4m望远镜观测系统进行大气消光和系统转换工作的初步结果。我们在2009年11月24日的观测夜，对Landolt标准星场进行了UBVRI五个光学波段的观测，然后利用IRAF软件对测光数据进行归化和校准处理，计算了五个波段的大气消光系数并给出了相关分析和结论。第六章是总结和展望。
英文摘要	In this thesis， we report the first results of a monitoring programme on a sample of 5 radio-loud narrow-line seyfert 1 (RL-NLS1) galaxies in order to search for microvariability in optical passbands (also named as intranight optical variability or intraday optical variability). Radio-loud narrow line Seyfert 1 galaxies are a scarce subclass of active galactic nuclei, which only make up 7% of the narrow line Seyfert 1 galaxies (NLS1s) known so far. Recently, of particular interest, RL-NLS1s were suggested to show multiwavelength properties typical of blazars (Yuan et al. 2008). The observational evidence includes compact VLBI cores, high brightness temperatures, flat radio spectra and rapid radio variability, and broad band spectral energy distributions similar to blazars. The gamma-ray radiation is also detected and interpreted as being emitted from relativistic jets by inverse Compton mechanism, presenting strong justification for the presence of jets in these objects . A natural prediction of this new picture is that at least some of the radio-loud NLS1s might exhibit, micro variability in optical, which is characteristic of non-thermal Doppler-boosted emission from jets, as commonly observed in blazars. In Chapter 2, we summarize the major observational properties and the general understanding of drivers and physics in this subclass of AGN. In Chapter 3, We describe the sample of RL-NLS1 galaxies of our study. In Chapter 4, we present the monitoring programme of the sample. The monitoring run was carried out in V and R bands on 7 observing nights. Large amplitude and rapid micro-variability was detected in five RL-NLS1s in both two optical bands on time-scales of several hours. The typical amplitude of variability of 2MASX J0324+3410, SDSS J1254+1141 and SDSS J0849+5108 are 0.1mag, 0.06mag and 0.25mag, respectively. The preliminary results of the other two objects are derived with clear optical microvariability of > 0.1mag. Our results indicate that the observed optical light of RL-NLS1 is significantly contributed by non-thermal emission, mostly likely from relativistic jets, as suggested by Zhou et al. (2007) and Yuan et al. (2008),as well as the most recent gamma-ray observations made with the GLAST Fermi satellite. In Chapter 5, we present the preliminary results of atmosphere extinction for the system of 2.4m telescope of Yunnan observatory at Gaomeigu observatory of Lijiang. We have carried out observations of Landolt's standard star field in UBVRI filters at 24th November, 2009. We derived the extinction coefficients for the above 5 pass bands and the transformations from the 2.4m photometric system to the standard Landolt magnitude system. We present the summary and prospects of our work in Chapter 6.
语种	中文
学科主题	天文学
页码	53
内容类型	学位论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/5091]
专题	云南天文台_高能天体物理研究组
推荐引用方式 GB/T 7714	时光. 射电噪窄线赛弗特 1型活动星系核的光学微光变监测[D]. 北京. 中国科学院研究生院（云南天文台）. 2011.

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