Collaborative Research: Understanding the limits of AGN feedback: a dedicated study of extremely high velocity outflows.

在不到一个世纪的时间里，我们对宇宙的认识已经从认为我们在宇宙中唯一的一个星系转变为认识到银河系之外还有数十亿个星系；今天我们还知道，大多数星系，如果不是全部的话，它们的中心都有一个超大质量黑洞。黑洞仍然是宇宙中最迷人的物体之一，虽然很难观察到它们，但向它们学习的一个方法是通过它们在环境中造成的影响。例如，只要周围有气体存在，这些超大质量黑洞就能“激活”宇宙中能量最高的现象之一：活动星系核，其中类星体是最亮的。在过去的二十年里，我们也了解到这些超大质量黑洞及其宿主星系的质量是相互关联的，但尚不清楚中央小区域和周围的巨大星系是如何将这一信息互通的。一种有希望的方法是通过外流，即从超大质量黑洞环境中排出的物质，可以到达银河系环境。外流还可以提供有关黑洞环境的物理和化学条件的关键线索。该项目将允许研究人员继续扩大已知的极高速类星体的样本，利用最先进的工具深入研究它们的整体性质以及最极端的情况，并利用所有这些信息来推进旨在说明这些外流如何从超大质量黑洞环境中发射的理论模型。该项目不可或缺的目标是提高未被充分代表的物理/天文学学生的入学、留住和毕业成功率，以帮助使未来STEM劳动力多样化。为了做到这一点，该团队在招收和支持学生、提供有偿研究和推广机会以及创建一个支持性社区方面仔细挑选了最佳实践。第2A部分最近发现的一类流出，极高速流出(EHVO)，可能是理解星系反馈过程的关键，因为它可能是质量能量方面最强大的：它似乎结合了超快流出的大速度和宽吸收线类星体中发现的大柱子密度。如果初步结果得到证实，EHVO类星体可能对确定观测到的活动星系核反馈信号的上限至关重要。该团队将进行一项全面的研究，其中包括：(1)通过将已经开发的工具应用于更大的类星体样本来扩大EHVO类星体的已知案例；(2)通过使用最先进的合成模型来研究总体样本属性和最极端的案例；以及(3)使用圆盘风模型计算合成光谱。他们定制了所有这些项目，以便团队可以与6-10名本科生一起实施，帮助培训未来一代科学家进行观测和理论类星体研究。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Part 1In less than one century, our knowledge about the universe has shifted from thinking that we were in the one and only galaxy in the universe to realizing that there are billions of galaxies beyond the Milky Way; today we also know that most galaxies, if not all, harbor in their centers a supermassive black hole. Black holes remain one of the most fascinating objects in the universe, and while they are difficult to observe, one way to learn from them is through the effects they cause in their environment. Whenever there is gas around them, for example, these supermassive black holes can "activate" one of the most energetic phenomena in the universe: active galactic nuclei, of which quasars are the most luminous ones. In the past two decades, we have also learned that the masses of these supermassive black holes and their host galaxies correlate, but it is not known how the small central region and the huge galaxy around "communicate" this information to each other. One promising method is through outflows, material expelled from the environment of the supermassive black hole that can reach the galactic environment. Outflows can also provide crucial clues about the physical and chemical conditions of the black holes' environment. This project will allow the researchers to continue enlarging the sample of known extremely high-velocity quasars, study their overall properties as well as the most extreme cases in depth by using state-of-the-art tools, and use all of this information to advance the theoretical models that aim to show how these outflows can be launched from the supermassive black hole environment. Integral to the project is the goal to increase access, retention, and graduation success for underrepresented physics/astronomy students, to help diversify the future STEM workforce. To do so, the team has carefully selected best practices in recruiting and supporting students, providing paid research and outreach opportunities, and creating a supportive community.Part 2A recently-discovered class of outflows, extremely high-velocity outflows (EHVO), may be key to understanding feedback processes in galaxies as it is likely the most powerful in terms of mass-energy: it seems to combine the large velocities of ultra-fast outflows and the large column densities found in broad absorption line quasars. If the preliminary results are confirmed, EHVO quasars might be crucial to determine the upper limit of observed AGN feedback signatures. The team will carry out a comprehensive study that includes (1) enlarging the known cases of EHVO quasars by applying already developed tools to a larger quasar sample, (2) studying the overall sample properties and the most extreme cases by using state-of-the-art synthetic modeling, and (3) computing synthetic spectra using disk wind models. They have tailored all of these projects so they can be carried out by the team together with 6 - 10 undergraduate students, helping train the future generation of scientists in both observational and theoretical quasar studies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.