Energetic electrons in the lobes of radio galaxies make them potential sources for not only radio and X-rays but also Sunyaev–Zeldovich (SZ) distortions in the cosmic microwave background (CMB) radiation. Previous works have discussed the energetics of radio galaxy lobes, but assuming thermal SZ effect, coming from the non-thermal electron population. We use an improved evolutionary model for radio galaxy lobes to estimate the observed parameters such as the radio luminosity and intensity of SZ-distortions at the redshifts of observation. We, further, quantify the effects of various relevant physical parameters of the radio galaxies, such as the jet power, the time-scale over which the jet is active, the evolutionary time-scale for the lobe, etc. on the observed parameters. For current SZ observations towards galaxy clusters, we find that the non-thermal SZ distortions from radio lobes embedded in galaxy clusters can be non-negligible compared to the amount of thermal SZ distortion from the intracluster medium and, hence, cannot be neglected. We show that small and young (and preferably residing in a cluster environment) radio galaxies offer better prospects for the detection of the non-thermal SZ signal from these sources. We further discuss the limits on different physical parameters for some sources for which SZ effect has been either detected or upper limits are available. The evolutionary models enable us to obtain limits, previously unavailable, on the low energy cut-off of electron spectrum (pmin ∼ 1–2) in order to explain the recent non-thermal SZ detection. Finally, we discuss how future CMB experiments, which would cover higher frequency bands (>400 GHz), may provide clear signatures for non-thermal SZ effect.

中文翻译：

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来自射电星系瓣的非热 Sunyaev-Zeldovich 信号

射电星系叶中的高能电子使其成为无线电和 X 射线以及宇宙微波背景 (CMB) 辐射中 Sunyaev-Zeldovich (SZ) 畸变的潜在来源。以前的工作已经讨论了射电星系瓣的能量学，但假设热 SZ 效应来自非热电子群体。我们使用改进的射电星系瓣演化模型来估计观测到的参数，例如观测红移处 SZ 畸变的射电光度和强度。我们进一步量化了射电星系的各种相关物理参数对观测参数的影响，例如射流功率、射流活跃的时间尺度、叶的演化时间尺度等。对于当前对星系团的 SZ 观测，我们发现嵌入星系团的射电瓣的非热 SZ 畸变与来自星系团内介质的热 SZ 畸变量相比是不可忽略的，因此不能忽略。我们表明，小而年轻（最好位于集群环境中）射电星系为检测来自这些来源的非热 SZ 信号提供了更好的前景。我们进一步讨论了一些源的不同物理参数的限制，这些源已经检测到 SZ 效应或有上限。进化模型使我们能够获得以前无法获得的电子光谱低能截止（pmin∼1-2）的限制，以解释最近的非热 SZ 检测。最后，我们讨论了未来的 CMB 实验如何覆盖更高的频段（>