Milliarcsecond Polarization Studies of Compact Extragalactic Radio Sources

AST 0098608 Wardle这个项目有两个组成部分：第一部分是研究非常遥远的星系和类星体中心区域的剧烈活动。这些天体的中心可能比一千个正常星系更明亮，是宇宙中最猛烈和最有活力的天体。 巨大的能量是由恒星和气体落入一个可能重达十亿个太阳的超大质量黑洞产生的。大部分的能量被集中到以接近光速运动的物质射流中。这些喷流辐射可见光、X射线和无线电波，这些都是可以观察到的。这项工作的目的是确定喷气机是由什么组成的，以及它们是如何聚焦的。最终目标是更好地理解大质量黑洞的物理学，以及它们如何产生能量。该项目的第二部分是使用这些类星体和星系来测量宇宙膨胀的速度。它们是如此明亮，以至于几乎可以看到可观测宇宙的边缘，并且可以追溯到宇宙非常年轻的时候。该项目将使用一种新的直接方法来测量这些类星体和星系的距离。希望是，当结合对它们远离我们的速度的测量时，这些将确定宇宙的膨胀率是加速还是减速。这一结果对于确定宇宙的年龄和了解宇宙的最早历史非常重要。该项目的资金由美国国家科学基金会的河外天文宇宙学计划（AST/EXC）提供。

AST 0098608WardleThis project has two components: The first part of this project is to study the violent activity in the central regions of very distant galaxies and quasars. The centers of these objects can be more brilliant than a thousand normal galaxies, and are the most violent and energetic objects in the universe. Enormous amounts of energy are generated by stars and gas falling into a super-massive black hole that may weigh as much as a billion suns. Much of the energy is focused into jets of matter moving at nearly the speed of light. These jets radiate visible light, x-rays and radio waves, which can be observe. This work aims to determine what the jets are made of, and how they are focused. The ultimate goal is to understand better the physics of massive black holes, and how they generate energy.The second part of this project is to use these same quasars and galaxies to measure how fast the universe is expanding. They are so bright that they can be seen almost to the edge of the observable universe, and back in time to when the universe was very young. This project will use a new and direct way of measuring the distances to these quasars and galaxies. The hope is that, when combined with measurements of their speed away from us, these will determine if the expansion rate of the universe is speeding up or slowing down. The result is important for finding the age of the universe, and for understanding the earliest history of the universe.Funding for this project was provided by the NSF program for Extragalactic Astronomy & Cosmology (AST/EXC).***