The many facets of black hole feedback in galaxies

在过去的几十年里，我们对宇宙的理解取得了巨大的进步。然而，我们仍然不明白星系-宇宙的基石-如何形成和演变与宇宙时间。从宇宙学模拟以及越来越多的观测证据中可以清楚地看到，超大质量黑洞在整个宇宙时间内调节恒星的形成方面发挥着根本和重要的作用。这在星系团的例子中已经得到了清楚的证明，在星系团中，来自中央超大质量黑洞的强大反馈阻止了热的团内气体灾难性地冷却，从而使预期的星星形成率降低了几个数量级。 然而，黑洞究竟如何释放能量，或者这种能量如何与周围环境相互作用，最终塑造星系的性质，仍然没有很好的理解。 该计划的长期目标是详细确定超大质量黑洞如何塑造星系的性质，特别关注了解黑洞喷流对其周围环境的影响;这是我们理解星系如何形成和随着宇宙时间演变的关键垫脚石。我打算在这一领域发挥关键作用，通过我在职业生涯中发展起来的久经考验的方法和良好的合作来解决这个问题。 目前的建议侧重于四个短期目标，这些目标基于哈勃空间望远镜和钱德拉X射线天文台等天基望远镜以及最近升级的甚大阵列和加拿大-法国-夏威夷望远镜等地面天文台的一系列新观测结果。这些观察结果中的大部分已经分配给我作为首席研究员。更具体地说，为了了解黑洞喷流与周围环境相互作用的各种方式，该提案将解决以下问题：从了解黑洞喷射流对黑洞影响范围内气体的影响（例如通过哈勃/STIS观测），了解黑洞喷流的正负反馈在星系尺度上的作用（例如通过观察黑洞喷流周围的多相气体），以及黑洞喷流对比其星系更大的尺度的影响（例如通过观察大尺度的漫射无线电同步辐射）和整个时间。这项科学的大部分目标将是星系团中心的黑洞，因为这些物体提供了一个环境，我们可以通过观察在X射线波长下可见的热的团内介质来直接见证黑洞喷流对星系周围环境的影响。 总的来说，这项提案有望在我的团队中，在加拿大以及在国际层面上实现尖端发现。

Our understanding of the Universe has progressed tremendously over the past decades. Yet, we still do not understand how galaxies - the building blocks of the Universe - form and evolve with cosmic time. What has become clear from cosmological simulations, as well as mounting evidence from observations, is that supermassive black holes play a fundamental and essential role in regulating the formation of stars throughout cosmic time. This has been clearly demonstrated in the case of galaxy clusters, in which powerful feedback from the central supermassive black hole is preventing the hot intracluster gas from cooling catastrophically; reducing the expected star formation rates by orders of magnitude. However, exactly how black holes release their energy or how this energy interacts with its surrounding, ultimately shaping the properties galaxies, is still not well understood. The long-term goal of this program is to determine in detail how supermassive black holes shape the properties of galaxies with a particular focus on understanding the impact of black hole jets on their surroundings; this is a key stepping-stone for our understanding of how galaxies form and evolve with cosmic time. I intend to play a pivotal role in this field by tackling the problem via well-tested methods and well-established collaborations that I have developed over my career. The current proposal focusses on four short-term objectives that are based on a series of novel observations from space-based telescopes such as the Hubble Space Telescope and the Chandra X-ray Observatory, as well as ground-based observatories such as the recently upgraded Very Large Array and the Canada-France-Hawaii telescope. Most of these observations have already been allocated to me as principal investigator. More specifically, to understand the various ways in which black hole jets interact with their surroundings, this proposal will address the following items: from understanding the impact of black holes jets on the gas within the spheres of influence of the black holes (e.g. via Hubble/STIS observations), to understanding the role of positive and negative feedback from black hole jets on the scale of their galaxies (e.g. via observations of the multiphase gas surrounding black hole jets), as well as the impact of black hole jets on scales larger than their galaxy (e.g. via observations of large-scale diffuse radio synchrotron emission) and throughout time. Most of this science will target the black holes at the centers of galaxy clusters because these objects provide an environment in which we can directly witness the impact of black hole jets on the environment surrounding galaxies via observations of the hot intracluster medium visible at X-ray wavelengths. Overall, this proposal promises to enable cutting-edge discoveries within my team, in Canada, as well as at the international level.