脉冲星的积分轮廓的高斯拟合及谱指数的研究

发布时间：2018-03-31 10:33

本文选题：脉冲星　切入点：谱指数　出处：《西南大学》2011年硕士论文

【摘要】：脉冲星的辐射机制是一个很有意义的课题,有多种研究方法,但到现在为止依然没有完全研究清楚。其中一种重要方法为利用脉冲星的积分轮廓流量的谱指数来探究脉冲星可能的辐射机制。脉冲星的积分轮廓是成百上千个单个脉冲按周期叠加累计而成,并且通常可以分解为多个高斯成分,可以通过高斯函数拟合。脉冲星的谱指数反应了脉冲星流量与观测频率之间的关系,通过它能很好的了解脉冲星的辐射机制。本论文通过选取欧洲脉冲星网站(The European Pulsar Network)的脉冲星观测数据,研究了脉冲星积分轮廓的高斯成分拟合,并且计算了每个成分及总轮廓的谱指数。该研究的主要目的首先在于通过谱指数的计算分析脉冲星的辐射机制,然后分析脉冲星各成分及总轮廓的谱指数是否一样,从而验证各成分的辐射机制是否一致。主要内容如下：第一章介绍了脉冲星研究的基本背景知识,脉冲星的研究现状,研究历史以及本课题研究的着眼点。第二章介绍了本论文所用的数据来源及其数据处理方法。第三章给出了我们选取的每个脉冲星轮廓的高斯拟合结果及每个高斯成分及总轮廓的谱指数,分析了每个脉冲星的轮廓及谱的性质。第四章对脉冲星的谱指数的进行统计研究。对于总流量的谱指数来说,小于－2的部分占14.8%,在－1到－2之间的脉冲星占了绝大部分,达到了74.1%,最后还有11.1%的脉冲星的谱指数在0到－1之间。还有少数脉冲星的谱出现了反转,低频的谱指数为正值。我们按谱指数的性质把谱分为了陡谱,平铺,低频反转等类型分别进行了讨论。我们还分析比较了脉冲星的各成分及总轮廓的谱指数的统计特征,发现各个成分的谱指数是和总流量的谱指数的分布情况非常一致。另外,对于单个脉冲星,发现当脉冲星总流量的谱指数在－2到－1之间时,一半以上的脉冲星各成分的谱指数不完全一致,说明各成分的辐射机制有可能不同。而对于陡谱指数和平谱指数的脉冲星,各成分的谱指数是趋于一致的,但这两类脉冲星样本较少。第五章给出了本文总结及研究展望。
[Abstract]:The radiative mechanism of pulsars is a significant subject, and there are many research methods, but up to now, it has not been fully studied.One of the important methods is to explore the possible radiative mechanism of pulsars by using the spectral index of the integral contour flux of pulsars.The integral profile of pulsars is accumulated by the periodic superposition of hundreds of single pulses, and can be decomposed into several Gao Si components, which can be fitted by Gao Si function.The spectral exponent of pulsar reflects the relationship between the flux of pulsar and the observed frequency, through which the radiation mechanism of pulsar can be well understood.In this paper, by selecting the pulsar observations from the European Pulsar Network, we study the fitting of the integral profile of the pulsar by Gao Si, and calculate the spectral index of each component and the total profile.The main purpose of this study is to analyze the radiative mechanism of pulsars through the calculation of spectral exponents, and then to analyze whether the spectral exponents of each component and total profile of pulsars are the same, so as to verify whether the radiation mechanism of each component is consistent or not.The main contents are as follows:The first chapter introduces the basic background of pulsar research, the status quo of pulsar research, research history and the focus of this research.The second chapter introduces the data sources and data processing methods used in this paper.In chapter 3, we give the fitting results of Gao Si for each pulsar contour, and the spectral index of every Gao Si component and total contour, and analyze the contour and spectral properties of each pulsar.In chapter 4, the spectral index of pulsars is studied.For the spectral index of the total flow, the fraction less than -2 accounts for 14.8.The pulse star between -1 and -2 accounts for the vast majority, reaching 74.1 percent. Finally, the spectral index of 11.1 percent pulsars is between 0 and 1.A few pulsars have reversed their spectra, and the low frequency spectral exponents are positive.According to the properties of spectral exponent, the spectrum is divided into steep spectrum, flat spectrum, low frequency inversion and so on.We also analyze and compare the statistical characteristics of spectral indices of each component and total contour of pulsars. It is found that the spectral indices of each component are in good agreement with the distribution of spectral indices of total flux.In addition, for a single pulsar, it is found that when the spectral index of the total flux of the pulsar is between -2 and -1, the spectral exponents of each component of more than half of the pulsars are not completely consistent, indicating that the radiation mechanism of each component may be different.For pulsars with steep spectral exponent and spectral exponent, the spectral indices of each component tend to be the same, but the samples of these two pulsars are less.The fifth chapter gives the summary and prospect of this paper.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：P145.6

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