Paving the Way for the First Direct Gravitational-Wave Discovery through Improved Noise Budgeting and Detector Characterization

通过改进噪声预算和探测器表征为首次直接引力波发现铺平道路

• 批准号: 1506497
• 负责人: Sukanta Bose
• 金额: $ 6万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2017-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1506497&HistoricalAwards=false
• 关键词: Paving; Way; First; Direct; Gravitational

The General Theory of Relativity discovered by Einstein tells us that the familiar, everyday force of gravity is a manifestation of something much stranger: the bending of the geometry of space-time by matter. Among the key predictions of the theory, which includes the expanding Universe and the existence of black holes, is the existence of gravitational waves (GW): ripples moving at the speed of light in the geometry of space-time caused by the fast motion of large masses. Although well tested in terms of their indirect effects on binary systems of compact stars, the direct detection of gravitational waves incident on Earth poses an outstanding challenge. The scientific rewards from achieving this ability would be enormous - ranging from probing the extreme dynamics of exploding stars to gleaning information about the state of the Universe almost at the moment of the Big Bang itself. The effort to enable this new window on the universe has occupied several decades of experimental and technological developments that have pushed the boundaries across diverse fields in the physical sciences. The year 2015 will mark a highly-anticipated watershed moment for gravitational-wave physics: The two advanced Laser Interferomenter Gravitational Wave Observatory (aLIGO) detectors will start their initial data taking runs, followed by the commissioning of the advanced Virgo gravitational wave observatory in Europe. The sensitivity of the aLIGO detector will be ramped up to become about ten times better than that of the first-generation detectors, opening up a spatial volume for observing GW sources that will be 1000 times larger than before. This award supports research that helps aLIGO to achieve design sensitivity in the coming years by contributing to a more complete accounting of sources of noise and characterization of the detectors. This will eventually lead to the publishing of GW data to the public with robust data quality flags. Supporting scientific discoveries by empowering the community at large is a primary goal of this project. Additionally, the researchers will continue to engage the faculty of the WSU campuses in Pullman and Tri-Cities to teach undergraduate students about GW science both through lectures and lab exercises. The latter campus caters to a large percentage of Hispanic and Native-American populations, both of which are under-represented, and offers a rare setting for integrating university education with cutting-edge research in gravitation being carried out at a nearby lab.The aLIGO detectors are being commissioned as we speak. These broadband detectors will also target the detection of GWs from multiple sources, such as binary black holes, spinning non-axisymmetric neutron stars, core collapse supernovae, and stochastic GW background of astrophysical or cosmological origins. They will accomplish this by resolving changes in the 4-km separations of its interferometric test mass optics that are a billionth the size of an atom. The WSU team will integrate the multiple new sensors that have been installed in aLIGO into the model of the interferometer noise budget and work on reducing any gap between its prediction and the observed noise floor.

爱因斯坦发现的广义相对论告诉我们，我们熟悉的、日常的引力是一种更奇怪的东西的表现：物质弯曲时空的几何形状。在该理论的关键预测中，包括膨胀的宇宙和黑洞的存在，是引力波（GW）的存在：由大质量的快速运动引起的时空几何中以光速移动的涟漪。虽然在它们对致密恒星双星系统的间接影响方面得到了很好的检验，但直接探测入射到地球上的引力波仍然是一个突出的挑战。实现这种能力的科学回报将是巨大的-从探测爆炸恒星的极端动力学到收集有关宇宙状态的信息几乎在大爆炸本身的时刻。为了实现这一新的宇宙窗口，已经花费了几十年的实验和技术发展，这些发展推动了物理科学各个领域的界限。2015年将是引力波物理学备受期待的分水岭：两个先进的激光干涉仪引力波天文台（aLIGO）探测器将开始其初始数据采集运行，随后是欧洲先进的处女座引力波天文台的调试。aLIGO探测器的灵敏度将提高到第一代探测器的10倍左右，为观测GW源开辟的空间体积将比以前大1000倍。 该奖项支持的研究，帮助aLIGO在未来几年内实现设计灵敏度，有助于更完整地说明噪声源和探测器的特性。这将最终导致GW数据向公众发布，并带有强大的数据质量标志。通过增强整个社区的能力来支持科学发现是该项目的主要目标。此外，研究人员将继续与普尔曼和三城的WSU校园的教师合作，通过讲座和实验室练习向本科生教授GW科学。后一个校园迎合了很大比例的西班牙裔和美国原住民人口，这两种人口的代表性都很低，并提供了一个罕见的环境，将大学教育与附近实验室正在进行的引力前沿研究相结合。这些宽带探测器还将探测来自多个来源的GW，例如双星黑洞，旋转非轴对称中子星，核心坍缩超新星以及天体物理或宇宙学起源的随机GW背景。他们将通过解决其干涉测试质量光学系统的4公里分离的变化来实现这一目标，这些光学系统的大小是原子的十亿分之一。WSU团队将把安装在aLIGO中的多个新传感器集成到干涉仪噪声预算模型中，并努力缩小其预测与观测到的噪声基底之间的差距。