Subjects: Astronomy >> Astrophysical processes submitted time 2022-08-30 Cooperative journals: 《天文研究与技术》
Abstract： The spectral energy distributions (SEDs) datas of Mrk421 are collected by our, a total of 73 states as research samples, and the single-region lepton model under the electron energy spectrum of the steady-state transition power law spectrum is applied. Then study the physical properties of Mrk421 jets during the light transition. Our main results are as follows: (1) there is an anticorrelation between magnetic B and Doppler δ in the sample, indicating that magnetic B and Doppler δ are interdependent in the Thomson region.(2) Electron spectral index p1 supports the interpretation of shock wave or magnetic reconnection during light variation of Mrk421.(3) There is a positive correlation between the synchronous peak frequency logνsynpk and the peak luminosity logνsynpkLsynpk, which means that there is an anti-flare variant sequence in the Mrk421 during the light change.(4) According to the equal partition parameter ε=UeUB (the ratio of relativistic electron energy density to magnetic field energy density), the electron energy and magnetic field energy of 26% of the states are nearly equal partition, The electron energy of 63% of the states is an order of magnitude larger than the magnetic field energy, The electron energy of 11% of the states is much larger than the magnetic field energy. This indicates that Mrk 421 is more likely to have the phenomenon that the electron energy is one order of magnitude larger than the magnetic field energy during the light change. It also means that the jets in the Mrk421 are dominated by particles; The relationship from Pe>PB, it is further shown that the Mrk421 jets are particle-dominated, PB≲Pr, meaning that the Poynting flux cannot account for the radiated power, The ranges of Pr/Pe from 0.01 to 0.51, shows that a small fraction of the relativistic electron energy may be used for the observed radiation. (5) Some ranges of the physical parameters of 3C 279 and Mrk421 may be relatively similar, but the physical processes inside the jets of these two sources may not be the same.
Subjects: Astronomy >> Astrophysical processes submitted time 2021-01-29 Cooperative journals: 《天文研究与技术》
Abstract：为了验证逆康普顿机制中的主导过程，以及主导过程中软光子的起源。我们通过文献收集了75个平谱射电类星体多波段的（准）同时性数据，并利用对数抛物线函数拟合了频谱能量分布，分析同步峰流量与逆康普顿峰之比和多普勒因子的关系，运用自举法计算了样本的种子因子分布用以调查软光子的起源。分析结果如下：(1)、在轻子模型框架下，整个样本与子样本log(〖U_B (νF_ν )〗_EC⁄〖U_ext (νF_ν )〗_syn )与logδ的显著相关性表明平谱射电类星体的高能辐射优先由外康普顿过程主导。(2)、对于相对低同步峰峰频的种群，观测的种子因子分布与理论上尘埃环的种子因子范围相交表明其逆康普顿过程中的软光子很可能由尘埃环主导，而对于相对高同步峰峰频的种群，观测的种子因子超过了宽线区或尘埃环种子因子的范围，因此我们还无法确定其软光子的来源。
Subjects: Astronomy >> Astrophysical processes submitted time 2021-09-29 Cooperative journals: 《天文研究与技术》
Abstract：搜集了3C 279的29个态的宽带能谱（Spectral Energy Distributions，SEDs）作为样本，使用稳态拐折幂律电子能谱分布（Electron Energy Distribution，EED）情况下的单区、均匀轻子模型进行拟合，进而研究该源光变时外在观测与内在物理特性及它们之间的关系。主要结果如下：（1）我们的结果支持光变的激波解释（但需要斜激波）或磁重联解释。（2）外康普顿（External Compton，EC）峰的峰值光度log〖ν_EC^pk L〗_EC^pk和磁场logB之间存在一个显著的反相关关系。多普勒因子logδ和外康普顿峰的峰值光度logν_EC^pk L_EC^pk之间存在正相关关系，意味着多普勒因子的增加是外康普顿峰的峰值光度升高的原因之一。（3）同步峰值频率logν_syn^pk和峰值光度logν_syn^pk L_syn^pk之间不存在显著的正相关关系，意味着反耀变体序列不一定对所有耀变体成立。（4）参数U_e/U_B（相对论电子能量密度与磁场能量密度的比值）远离1，说明相对论电子与磁场之间均分趋势不明显，并且参数U_e/U_B中比值大于1的占86%，意味着3C 279中的喷流大多数以粒子为主导；从P_B （磁场功率）0.5表明3C 279喷流中的能量大概率也是由冷质子携带的。同时，我们发现3C 279中γ-ray耗散区位于距离黑洞中心0.1~1.8pc处，暗示着它们位于宽线区（Broad-Line Region，BLR）之外，尘埃环（Dusty Torus，DT）之内。
Subjects: Astronomy >> Astrophysical processes submitted time 2019-09-18 Cooperative journals: 《天文研究与技术》
Abstract： 使用了一个具有（准）同时性宽带能谱数据的Fermi耀变体样本，对其进行了同步和逆康普顿峰峰值参量、康普顿主导以及高能谱指数等参量之间的相关性分析。以获得耀变体整体和子类相关性之间差异来源、耀变体喷流中粒子冷却的主导机制，和电子能谱形状等方面的解释。分析结果表明耀变体的整体相关性至少有部分来自于平谱射电类星体和BL Lac天体由于物理性质不同而在参数平面上具有不同分布区域这一特性贡献，因此针对两个子类的相关性分析是必需的。BL Lac天体为快冷却机制。谱指数图的结果支持对数抛物线形状的电子能谱。
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