伽玛射线暴X射线余辉的光变和谱性质研究
发布时间：2018-09-05 09:32
【摘要】：伽玛射线暴(简称伽玛暴)是宇宙中最猛烈的Y射线爆发现象。在Y射线爆发爆发之后,一般能够观测到X射线耀发。一般认为X射线耀发起源于中心引擎的晚期活动,产生于相对论性的火球中。本论文对X射线耀发的光变曲线、谱演化进行了系统的研究。同时,也研究了具有X射线鼓包成分的伽玛暴属性。第一章,简要介绍了伽玛暴观测和理论上的研究进展。结合本人硕士期间所开展的工作,第二章详细介绍了Swift时期伽玛暴的研究进展。第三章,介绍了我们对于X射线耀发下降段的研究工作。在曲率效应模型框架下,我们对29个比较亮的X射线耀发的光变曲线和谱指数的演化行为进行了联合拟合,估算了X射线耀发的洛伦兹因子和辐射区位置。结果显示,我们所研究的X射线耀发,其快速下降段的特征时标大约在35秒到351秒,而洛伦兹因子在10到78之间。基于此可以估计出X射线耀发的辐射区位置,也就是：Rx～7.1×1014至2.7×1016cm。这个结果显示,X射线耀发发生的位置比X射线耀发时间处的余辉位置靠内。第四章,介绍了我们对于具有X射线鼓包成分的伽玛暴所开展的研究工作。从光变和谱两个角度,我们系统分析了所找到的这些暴的X射线鼓包成分。发现鼓包成分的谱指数基本不随时间演化；另外,光变曲线可以用多成分的幂律函数进行拟合。对X射线鼓包、光学起始鼓包以及光学晚期增亮鼓包的参数进行比较,发现它们基本一致,也就是：峰值光度和半宽均和时间有紧密的相关性,分别为Lp∝tp-0.71±0.07和w∝tp0.94±0.07。最后,假定x射线鼓包起源于伽玛暴瞬时辐射火球的减速,对于有红移观测的源,我们估算了伽玛暴瞬时辐射的洛伦兹因子和辐射效率,分别在20到130及0.02%到3.55%的范围内。
[Abstract]:Gamma-ray burst (gamma-ray burst) is the most violent Y-ray burst in the universe. X-ray flares are generally observed after Y-ray bursts. X-ray flares are thought to originate from late central engine activity and from relativistic fireballs. In this paper, the optical curve and spectral evolution of X-ray flares are systematically studied. At the same time, the gamma-ray burst properties with X-ray tympanic composition are also studied. In the first chapter, the research progress of Gamma-ray burst observation and theory is briefly introduced. In the second chapter, the research progress of Gamma burst during Swift period is introduced in detail. In the third chapter, we introduce our research work on the falling section of X-ray flares. In the framework of curvature effect model, the phototropic curves of 29 bright X-ray flares and the evolution of spectral exponents are fitted together, and the Lorentz factor and the location of radiation region of X-ray flares are estimated. The results show that the characteristic time scale of the rapid descent of the X-ray flares is about 35 seconds to 351 seconds and the Lorentz factor is between 10 and 78 seconds. Based on this, the location of the radiation region of the X-ray flares can be estimated, that is, 7. 1 脳 1014 to 2. 7 脳 10 ~ (16) cm ~ (-1) of the X ray flares. The results show that the position of the X ray flares is inward than that of the afterglow at the time of the X ray flares. In chapter 4, we introduce our research work on gamma bursts with X-ray tympanic composition. From the point of view of light variation and spectrum, we have systematically analyzed the X-ray tympanic compositions of these storms. It is found that the spectral exponent of the bulge component does not evolve with time, and that the optical variation curve can be fitted by the power law function of multiple components. By comparing the parameters of X-ray bulge, optical initial tympanic bag and late optical brightening drum, it is found that they are basically the same, that is, the peak luminosity and half width are closely correlated with time, which are Lp 鈭，
本文编号：2223875
[Abstract]:Gamma-ray burst (gamma-ray burst) is the most violent Y-ray burst in the universe. X-ray flares are generally observed after Y-ray bursts. X-ray flares are thought to originate from late central engine activity and from relativistic fireballs. In this paper, the optical curve and spectral evolution of X-ray flares are systematically studied. At the same time, the gamma-ray burst properties with X-ray tympanic composition are also studied. In the first chapter, the research progress of Gamma-ray burst observation and theory is briefly introduced. In the second chapter, the research progress of Gamma burst during Swift period is introduced in detail. In the third chapter, we introduce our research work on the falling section of X-ray flares. In the framework of curvature effect model, the phototropic curves of 29 bright X-ray flares and the evolution of spectral exponents are fitted together, and the Lorentz factor and the location of radiation region of X-ray flares are estimated. The results show that the characteristic time scale of the rapid descent of the X-ray flares is about 35 seconds to 351 seconds and the Lorentz factor is between 10 and 78 seconds. Based on this, the location of the radiation region of the X-ray flares can be estimated, that is, 7. 1 脳 1014 to 2. 7 脳 10 ~ (16) cm ~ (-1) of the X ray flares. The results show that the position of the X ray flares is inward than that of the afterglow at the time of the X ray flares. In chapter 4, we introduce our research work on gamma bursts with X-ray tympanic composition. From the point of view of light variation and spectrum, we have systematically analyzed the X-ray tympanic compositions of these storms. It is found that the spectral exponent of the bulge component does not evolve with time, and that the optical variation curve can be fitted by the power law function of multiple components. By comparing the parameters of X-ray bulge, optical initial tympanic bag and late optical brightening drum, it is found that they are basically the same, that is, the peak luminosity and half width are closely correlated with time, which are Lp 鈭，
本文编号：2223875
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