Blazar天体的复合谱指数特性研究

【作者】 唐玲；

【导师】 张雄；

【作者基本信息】 云南师范大学 ， 天体物理， 2009， 硕士

【摘要】 本文概述了Blazar天体的辐射理论模型、多波段能谱特征,光变特性。收集了66个有γ射线噪的Blazar在高态下的多波段流量数据,研究了Blazar复合谱指数之间的相关性。分析了BL Lac天体和平谱射电类星体（FSRQs）复合谱指数之间的相关性。结果表明（1）高态下Blazar的复合谱指数α_r,ir,与α_ir,γ、α_r,ir与α_o,γ、α_r,o与α_o,x、α_r,o与α_o,γ之间有强相关性。α_r,x与α_x,γ之间有强负相关性。（2）平谱射电类星体（FSRQs）在高态下α_r,o与α_o,x、α_r,o与α_o,γ有强相关性。（3）BLLac天体在高态时α_r,o与α_o,γ之间有强相关性。（4）α_r,x与α_x,γ、α_ir,x与α_x,γ有强负相关性。（5）γ射线很可能产生于同步自康普顿（ssc）过程。用功率谱方法和小波分析方法寻找BL Lac天体S5 0716+714光变周期,收集了BL Lac天体S5 0716+714光学B、V、R、I四个波段较完备的观测数据,获得了天平均的复合谱指数,用复合谱指数计算了S5 0716+714长周期变化,表明复合谱指数的变化也具也周期性。利用功率谱的方法得到了复合谱指数变化周期和光学波段流量的变化周期都是1280天。从小波变换系数实部的等值线图,可以准确证认BL Lac天体S5 0716+714有光变周期波动变化,由复合谱指数小波方差曲线分析发现BL Lac天体S5 0176+714有一个1180天的稳定周期,这个结果与Raiter等人发现的3.3年周期是一致的。本文通过研究大样本天体和单一样本的复合谱指数,分析研究了Blazar天体的复合谱指数特性。更多还原

【Abstract】 In this paper,we illuminate theoretical radiation model,spectral energy distributions and characters of variability of blazars.Using the broad band spectral index of 66 gamma-ray-loud blazars in a high state,we studied the possible correlations between different broad band spectral index.We also studied the possible correlation between different broad band spectral index of BL Lac object and flat spectral radio quasars（FSRQs）,respectively.（1）The strong correlations were found betweenα_r.ir andα_ir.γ,betweenα_r.ir andα_o.γ,betweenα_r.o andα_o.x and betweenα_r.o andα_o.γ in a high state for our blazars sample.（2）The strong anti-correlations were found betweenα_r.x andα_x.γ in a high state for our blazars sample.（3）For flat spectral radio quasars（FSRQs） the strong correlation were found betweenα_r.o andα_o.x and betweenα_r.o andα_o.γ in a high state.（4）For BL Lac object the strong correlations were found betweenα_r.o andα_o.γ,the strong anti-correlations were found betweenα_r.x andα_x.γ and betweenα_ir.x andα_x.γ in a high state.（5）Based on these results,we suggested that theγ-ray emission is probably from the self-Compton process.We employ the Fourier transform spectral analysis and wavelet analysis technique which are used to find the periodicities of optical spectral index with the BL Lac object S5 0716+714.By collected entirety observation results of the BL Lac class object S5 071.6+714 in B,V,R and I bands,we can calculate the daily optical spectral index of S5 0716+714 using data from the literature.We find that the optical spectral index variability period of BL Lacertae object 0716+714.Fourier transfrom spectral analysis which is used to find the periodicities of optical spectral index and optical variability periodicities are 1180 days.From the contour map of the coefficient transformed of real part,the results of the wavelet analysis can be obtained that there exists a change of optical variations in S5 0716+714,and by the research of the wavelet variance curve,S5 0716+714 has a stable periodicities on 1180 days,this outcome is consistent with 3.3 years period which is found by Raiter.In this thesis,we analyze properties of the broad band spectral index of blazar by studying large samples of objects and a single sample the broad band spectral index of blazer.更多还原