Are Active Galactic Nuclei accretion disks too big?

第1部分所有主要的星系似乎都有一个超大质量的黑洞，质量是我们太阳的数百万倍，居住在它们的中心。 这些黑洞对它们的宿主星系的生长和演化有着重要的影响。 黑洞增长的一个重要方式是通过一个称为吸积的过程，其中热气通过一个圆盘螺旋进入黑洞。 最近的研究表明，这些吸积盘比理论预期的要大好几倍。 由于这些天体距离太远，天文学家无法直接拍摄到圆盘本身的照片，因此必须使用间接技术。 在这个项目中，PI将使用一种称为混响映射的技术。 它利用光的回声来确定吸积盘的大小，就像声纳利用声音的回声来绘制海底地图一样。 使用专用的机器人望远镜，PI将每年监测大约10个超大质量黑洞吸积盘，以测试为什么吸积盘看起来太大，并更好地了解黑洞如何生长。 在更广泛的影响领域，PI将把这个项目的科学融入底特律当地的学校。第二部分超大质量黑洞在它们所在的星系的生长和演化中起着重要的作用。 它们生长的一个主要方式是通过气体经由盘的吸积。然而，对这些吸积盘结构的观测探测是罕见的，特别是因为它们太小太远，无法直接在空间上分辨。 在这个项目中，PI将使用一种被称为混响映射的技术，该技术测量光的回声以确定吸积盘的大小。最近使用这种技术的几项研究表明，这些磁盘比预期大2 - 3倍。 为了更好地理解这一点，我们将使用一个专用的机器人望远镜，每年监测大约10个超大质量黑洞吸积盘，建立一个实质性的样本。此外，PI将应用新的分析技术来进一步测试回波的起源，并测试为什么这些吸积盘看起来太大。 在更广泛的影响方面，PI将把该项目的科学融入底特律当地的学校。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Part 1All major galaxies appear to harbor a supermassive black hole, millions of times the mass of our Sun, residing at their center. These black holes have an important influence over the way their host galaxies grow and evolve. An important way in which the black hole grows is through a process called accretion, where hot gas spirals into the black hole via a disk. Recent studies suggest that these accretion disks are several times larger than expected by theory. As these objects are so distant astronomers cannot take direct pictures of the disks themselves and so must use indirect techniques. In this project, the PI will use a technique called reverberation mapping. This uses echoes of light to determine the size of the accretion disks, much like sonar uses echoes of sound to map the ocean floor. Using a dedicated robotic telescope the PI will monitor approximately 10 supermassive black hole accretion disks per year to test why accretion disks appear too big, and better understand how black holes grow. In the area of Broader Impacts, the PI will integrate the science of this project into local Detroit schools.Part 2Supermassive black holes play an important role in the growth and evolution of the galaxies in which they reside. A principal way in which they grow is via the accretion of gas via a disk. However, observational probes of the structure of these accretion disks are rare, especially since they are too small and distant to spatially resolve directly. In this project, the PI will use a technique known as reverberation mapping which measures echoes of light to determine the size scale of the accretion disks. Several recent studies using this technique suggest that these disks are a factor of 2 - 3 larger than expected. To better understand this we will use a dedicated robotic telescope to monitor approximately 10 supermassive black hole accretion disks per year building a substantial sample. Furthermore, the PI will apply novel analysis techniques to further test of origin of the echoes, and test why these accretion disks appear too big. In the area of Broader Impacts, the PI will integrate the science of this project into local Detroit schools.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.