The origin of radio emission in broad absorption line quasars (BALQSOs)

本项目将研究宽吸收线类星体（BALQSO）射电辐射的起源。大多数BALQSO在无线电频率下观测时都很微弱，我们对它们的无线电发射知之甚少。新的灵敏无线电仪器和调查正在改变这一点，我们可以开始在理解宽吸收线类星体的无线电发射以及黑洞周围的吸积和流出物理学方面取得重大进展。与宽吸收线和射电辐射相关的性质之间的相关性意味着一种联系-但这是从哪里来的呢？射电辐射是由外流本身产生的，还是仅仅与驱动整个过程的中央类星体有关？詹姆斯将使用LOFAR两米巡天（LoTSS）的新数据探索这些问题，用于宽吸收线类星体的统计研究。基于数据发布1（Morabito et al. 2019）的已发表结果，他将在数据发布2中扩展这项工作，将样本量增加近一个数量级。他将比较观测趋势与玩具模型，以区分类星体的演化模型和几何模型。此外，詹姆斯将以更高的分辨率（0.26角秒，而不是6角秒）重新处理LOFAR数据，以发现BALQSO的无线电形态。最后，他将使用流体动力学模型的输出，将它们与观测结果进行比较，以确定是盘风还是喷流产生了无线电发射。詹姆斯将学习可转移的技能，如处理大型数据集，在集群环境中计算，以及如何将物理定律转化为编程语言。他还将有机会准备望远镜时间的建议，如果时间允许，他可能会去观察。

This project will investigate the origin of radio emission in broad absorption line quasars (BALQSOs). Most BALQSOs are faint when observed at radio frequencies, and we do not know much about their radio emission. New sensitive radio instruments and surveys are changing this, and we can start to make major advances in understanding the radio emission in broad absorption line quasars and the physics of accretion and outflows around black holes. Correlations between properties related to the broad absorption lines and the radio emission imply a connection - but where does this come from? Is the radio emission generated by the outflows themselves, or merely related to the central quasar driving the entire process? James will explore these questions using new data from the LOFAR Two-metre Sky Survey (LoTSS) for statistical studies of broad absorption line quasars. Building on published results from data release 1 (Morabito et al. 2019), he will expand this work with data release 2, increasing the sample size by almost an order of magnitude. He will compare observational trends with toy models to distinguish between evolutionary and geometric models of quasars. In addition, James will re-process LOFAR data at higher resolution (0.26 arcsec compared to 6 arcsec) to discover the radio morphology of BALQSOs. Finally, he will work with the outputs of hydrodynamical models, comparing them with the observations to determine whether disk winds or jets are creating the radio emission. James will learn transferable skills such as dealing with large data sets, computing in a cluster environment, and how to translate physical laws into programming language. He will also have a chance to prepare proposals for telescope time and potentially go observing if the time is granted.