Blazar天体的光变及其周期性分析

发布时间：2018-05-26 15:12

本文选题：活动星系核(AGNs) + 光变周期　；参考：《云南师范大学》2015年硕士论文

【摘要】：活动星系核(AGNs)是现代天体物理学中最有价值的研究领域之一。Blazar天体是AGNs的一个部分,其光变性质的不同,反映了它的性质、结构以及内部物理过程的不同。所以,研究Blazar天体的光变可以帮助我们更多地去了解活动星系核的物理本质特征,能够得到关于这类天体活动机制的有用信息,这对研究AGNs模型有着重要的意义。在本文当中,首先介绍了活动星系核的相关知识;其次,介绍了Blazar天体的光变以及光变的分类,光变可分为短时标光变、中时标光变和长周期光变三类,本文主要研究的是Blazar天体的长周期光变和光变周期的计算。第三章,介绍了分析Blazar天体光变周期的几种方法。目前比较成熟的方法有:Jurkevich方法、小波分析方法、结构函数法、功率谱法、离散相关函数分析方法等;在第四章中,先简单提了一下应用到信号分析当中的傅立叶变换分析方法,包括连续傅立叶变换和离散傅立叶变换。下面将介绍周期分析的另外一种方法,就是Period04分析方法,它是目前天文界尤其是脉动变星研究中最常用的分析软件之一。在介绍的过程中,描述了谱分析软件Period04的界面和功能,以及用它进行周期分析的步骤。最后,在第五章中研究了Period04方法在活动星系核光变周期中的实际应用。搜集了类星体3C 273和BL Lac天体OJ 287的长期光变观测数据,在此基础上用Period04软件对观测数据进行周期分析,并获得可信度较高的周期结果,得出的周期跟其他作者用不同方法得出的结果基本一致。然后用算出的周期再次拟合观测数据做一个周期反演,周期拟合曲线与观测数据的爆发周期规律基本一致,说明得出的周期是比较可靠的。通过得出的周期可以估算其中心黑洞质量和不稳定性发生区域的半径。结果表明:将Period04方法应用到Blazar天体的周期分析研究上是比较可靠的。
[Abstract]:Active Galactic Nucleus (AGNs) is one of the most valuable research fields in modern astrophysics. Blazar is a part of AGNs. The difference of its photonic properties reflects the difference of its properties, structures and internal physical processes. Therefore, the study of the light variation of Blazar celestial bodies can help us to understand the physical characteristics of AGNs and obtain useful information about the active mechanism of AGNs, which is of great significance to the study of the AGNs model. In this paper, we first introduce the relevant knowledge of the active galactic nucleus, secondly, we introduce the light variation and the classification of the Blazar celestial body, which can be divided into three types: short time scale light change, medium time scale light change and long period light change. In this paper, we mainly study the calculation of long period light variation and optical variation period of Blazar celestial body. In the third chapter, several methods of analyzing the period of Blazar celestial body are introduced. At present, there are more mature methods such as: Jurkevich method, wavelet analysis method, structure function method, power spectrum method, discrete correlation function analysis method, etc. In the fourth chapter, the Fourier transform analysis method which is applied to signal analysis is briefly mentioned. It includes continuous Fourier transform and discrete Fourier transform. Another method for periodic analysis is the Period04 method, which is one of the most commonly used analytical software in astronomical research, especially in the study of pulsating variable stars. In the course of introduction, the interface and function of spectrum analysis software Period04 are described, and the steps of using it to carry out periodic analysis are described. Finally, in Chapter 5, the practical application of the Period04 method in the period of light variation of AGNs is studied. The long-term photovariation data of the quasars 3C 273 and BL Lac object OJ287 are collected. On the basis of these data, the periodic analysis of the observed data is carried out by using Period04 software, and the reliable periodic results are obtained. The resulting cycle is basically consistent with the results obtained by other authors in different ways. Then a periodic inversion is made by using the calculated period to fit the observed data again. The periodic fitting curve is basically consistent with the law of the burst cycle of the observed data, which shows that the obtained period is relatively reliable. The mass of the central black hole and the radius of the region of instability can be estimated by the period obtained. The results show that it is reliable to apply the Period04 method to the periodic analysis of Blazar objects.
【学位授予单位】：云南师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P157.7

【共引文献】