Radio-loud AGN in the first LoTSS data release The lifetimes and environmental impact of jet-driven sources
Radio-loud AGN in the first LoTSS data release The lifetimes and environmental impact of jet-driven sources
复制标题
第一个 LoTSS 数据发布中的无线电响 AGN 喷气驱动源的寿命和环境影响
DOI：
10.1051/0004-6361/201833893
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发表时间：
2019
影响因子：
6.5
通讯作者：
Hardcastle M
中科院分区：
文献类型：
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作者：
Hardcastle M
我们从LOFAR对Hetdex Spring场的两米天空调查(LoTSS)得出的星表中构建了23344个射电活动星系核(RLAGN)的样本。尽管将活动星系核从恒星形成星系中分离出来仍然具有挑战性，但我们使用的光谱和光度学技术的结合为我们提供了候选RLAGN的最大样本之一。我们利用样品，结合最近发展的分析模型，研究了RLAGN的寿命分布。我们发现，大的或巨大的强RLAGN很可能是普通RLAGN种群的老尾巴，但我们样本中的低光度RLAGN候选天体，其中许多大小为<；100kpc，要么需要非常不同的寿命分布，要么具有与更强天体不同的喷流物理。然后，我们使用分析模型开发了一种估计候选对象的喷流运动功率的方法，并基于这些估计构建了喷流运动光度函数。这些值可以与观测量相比较，例如群和星系团的综合辐射光度，也可以与星系形成和演化中的RLAGN反馈模型的预测相比较。特别地，我们证明了局域宇宙中的RLAGN能够提供单位转动体积所需的所有能量，以抵消来自群和星团的X射线辐射损失，从而防止热气体冷却。我们对局部RLAGN的动力学光度密度的计算与最近的其他观测估计和星系形成的模型很好地一致。
We constructed a sample of 23 344 radio-loud active galactic nuclei (RLAGN) from the catalogue derived from the LOFAR Two-Metre Sky Survey (LoTSS) survey of the HETDEX Spring field. Although separating AGN from star-forming galaxies remains challenging, the combination of spectroscopic and photometric techniques we used gives us one of the largest available samples of candidate RLAGN. We used the sample, combined with recently developed analytical models, to investigate the lifetime distribution of RLAGN. We show that large or giant powerful RLAGN are probably the old tail of the general RLAGN population, but that the low-luminosity RLAGN candidates in our sample, many of which have sizes < 100 kpc, either require a very different lifetime distribution or have different jet physics from the more powerful objects. We then used analytical models to develop a method of estimating jet kinetic powers for our candidate objects and constructed a jet kinetic luminosity function based on these estimates. These values can be compared to observational quantities, such as the integrated radiative luminosity of groups and clusters, and to the predictions from models of RLAGN feedback in galaxy formation and evolution. In particular, we show that RLAGN in the local Universe are able to supply all the energy required per comoving unit volume to counterbalance X-ray radiative losses from groups and clusters and thus prevent the hot gas from cooling. Our computation of the kinetic luminosity density of local RLAGN is in good agreement with other recent observational estimates and with models of galaxy formation.