Dynamical Age vs Spectral Age of the Lobes of Selected Giant Radio Sources (GRSs)
J. Machalski, M. Jamrozy, D. J. Saikia
备注：
To appear in ASP Conference Series, Vol. 407, The Low-Frequency Radio Universe, eds D. J. Saikia, D. A. Green, Y. Gupta and T. Venturi (Conference held at NCRA, Pune, India from 8th to 12th December 2008)
Dynamical ages of the opposite lobes determined {\sl independently} of each other suggest that their ratios are between $\sim$1.1 to $\sim$1.4. Demanding similar values of the jet power and the radio core density for the same GRS, we look for a {\sl self-consistent} solution for the opposite lobes, which results in different density profiles along them found by the fit. A comparison of the dynamical and spectral ages shows that their ratio is between $\sim$1 and $\sim$5, i.e. is similar to that found for smaller radio galaxies. Two causes of this effect are pointed out.
The energetics of giant radio galaxy lobes from inverse Compton scattering observations
巨射电星系（GRG）叶是研究粒子演化和B场能量学的极好实验室。然而，这些结果是基于假设的形状和扩展的GRG波瓣电子光谱。我们重新检查GRG瓣的能量学，通过RG瓣中的相对论电子对CMB光子的逆康普顿散射（ICS-CMB）来评估RG瓣的物理条件，它们的能量学和它们的辐射制度。我们认为GRG DA 240最近观察到的朱雀作为一个参考案例，我们也讨论了其他RG叶观察钱德拉和XMM。利用从射电到伽玛射线的多频信息，对DA 240东瓣的能量分布进行了建模，得到了对电子能谱形状和扩展的约束。我们使用无线电和X射线数据来约束电子光谱的形状和归一化，然后计算对总电子能量密度敏感的GRG瓣中预期的SZ效应。我们表明，由X射线观测得到的电子能量密度U_e仅比实际值有一个粗略的下限，而且考虑到较低的电子动量p_1的实际估计，大多数基于X射线测量的U_e估计值都必须增加一个很大的因子。这使得RG波瓣远离均分条件，朝向粒子主导和康普顿功率主导的状态。我们使用RG波瓣在U_e/U_B与U_e/U_CMB平面上的分布作为RG波瓣中粒子和场主导以及辐射机制主导的不同物理状态之间的进一步划分。我们的结论是，在RG叶中观察到的ICS-CMB机制产生的SZ效应提供了可靠的p_1和U_e的估计，是确定RG叶的总能量密度和评估其物理状态的最佳工具。
A multifrequency study of giant radio sources III. Dynamical age vs. spectral age of the lobes of selected sources
用Machalski等人的DYNAGE算法估算了选定的巨射电源对瓣的动力学年龄，并与Jamrozy等人在论文II中估计和研究的光谱年龄进行了比较。正如预期的那样，DYNAGE拟合给出了彼此独立建模的相对叶的略微不同的动力学年龄和其他模型参数，例如年龄比在~1.1到~1.4之间。相同的源，要求类似的值的喷流功率和无线电核心密度，我们寻找一个自洽的解决方案，为相反的叶，这导致不同的密度分布沿他们发现的拟合。我们还表明，偏离均分条件假设在模型中，合理的X射线观测的叶片附近的一些射电星系，和相关的变化的磁场强度可能提供一个均衡的叶片的年龄。动力学年龄和光谱年龄的比较表明，所研究的巨型射电星系的动力学年龄与光谱年龄的比值在~1和~5之间，即与较小的射电星系相似（例如Parma et al. 1999）。补充了文献中已经讨论过的这种效应的可能原因，如模型假设参数的不确定性，可能偏离能量均分假设的影响等。给出的论据表明，DYNAGE算法可以更好地考虑在较低频率下的辐射效应比光谱老化分析。DYNAGE算法是特别有效的在高红移源，其固有频谱曲率向低频移动。
On The Depolarization Asymmetry Seen in Giant Radio Lobes
在双瓣射电源中看到的去极化不对称性，被称为莱恩-加灵顿（L-G）效应，其中随着波长的增加，在没有可见喷流的瓣中看到更快速的去极化，可以通过两个瓣之间的内部差异来解释，或者通过仅位于去极化瓣前面的外部法拉第屏来解释。如果喷流的单侧性是由于相对论性光束，那么退偏振不对称性一定是由于法拉第屏的介入。如果它是内在的，去极化不对称性必须与叶的内部差异有关。在本文中，我们假设几个Fanaroff-Riley Class 1（FRI）源的外喷流的速度表现出L-G效应是接近的0.1c由其他几个研究者报告。对于这些来源，我们发现，喷流的片面性不能解释的光束，因此必须是内在的。在这些FRI源中，L-G效应必须归因于起源于叶本身内部的差异。虽然不知道FRII源的外部喷流中的流动是否也减慢到这个速度，但建议对L-G效应的解释在两种类型中可能是相同的。最近的证据表明FRII星系具有非常大的视角，这反过来又意味着L-G模型不能与喷流速度无关。因此，完全排除脑叶的内部去极化作为L-G效应的真正解释可能还为时过早。
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Current and upcoming high angular resolution and multi-frequency experiments are well poised to explore the rich landscape of secondary CMB anisotropies. In this context, we compute for the first time, the power spectrum of CMB fluctuations from a cosmological distribution of evolving lobes of giant radio galaxies. We, also, explicitly take into account the non-thermal electron distribution, which has important implications for the inference of the CMB angular power spectrum. We calculate the mean global non-thermal y-distortion, \ynt. For observationally reasonable distribution of the jet lum…
