RUI: Stochastic Background Searches with the LIGO and ALLEGRO Detectors

激光干涉仪引力波天文台（LIGO）目前正处于科学数据收集的阶段，其间穿插着逐步提高灵敏度的调试活动。位于巴吞鲁日的路易斯安那州立大学运行的ALLEGRO共振质量引力波探测器位于距离LIGO利文斯顿天文台（LLO）约40公里的地方。该探测器自从搬到一个新的实验室后进行了重大整修，在进行这项活动的同时也进行了数据收集。LLO和ALLEGRO探测器的接近为寻找引力辐射提供了一个独特的机会。这项研究的主要重点是利用这种接近性来寻找引力波的随机背景。ALLEGRO具有以最小的干扰旋转探测器的能力。这将允许信号调制通过对准和错对准探测器与LLO干涉仪臂。这允许去除任何不具有引力辐射预期的四极空间依赖性的相关噪声。该项目代表了对数据分析挑战的继续研究，利用ALLEGRO-LLO对探测器寻找引力波的随机背景，作为对LIGO其他此类搜索的补充。如果我们目前对宇宙的理解是正确的，那么几乎可以肯定，在某种程度上存在着引力波的随机背景，这些引力波起源于暴胀的残余，早期宇宙的相变，或者来自大量离散源的混乱极限。在这样一个背景上的观测或上限给我们带来了关于宇宙的新信息。该项目将对路易斯安那州主要本科院校新奥尔良洛约拉大学的教育环境产生影响。该项目将在洛约拉保持一个充满活力的研究活动，同时纳入本科生作为研究助理。

The Laser Interferometer Gravitational wave Observatory (LIGO) is currently in a phase of sci-entific data collecting interspersed with commissioning activities that are incrementally improvingthe sensitivities. The ALLEGRO resonant mass gravitational wave detector operated by Louisiana State University in Baton Rouge is located about 40 kilometers from the LIGO Livingston Observatory (LLO). The detector has undergone major renovation since being moved to a new laboratory and has also had periods of data collection interspersed with this activity. The proximity of the LLO and ALLEGRO detectors allows for a unique opportunity in the search for gravitational radiation. The primary focus of this research is to exploit this proximity to search for a stochastic background of gravitational waves. ALLEGRO has the ability to rotate the detector with a minimum of disruption. This will allow a modulation of the signal by aligning and mis-aligning the detector with the LLO interferometer arms. This allows for the removal of any correlated noise that does not have the expected quadrupolar spatial dependence of the gravitational radiation. This project represents the continuation of research to pursue the data analysis challenges in searching for stochastic background of gravitational waves with the ALLEGRO-LLO pair of detectors as a complement to other such searches in LIGO.If our current understanding of the Universe is correct, there almost certainly exists a stochastic background of gravitational waves at some level, originating as a remnant of inflation, a phase transition in the early universe, or from the confusion limit of a large number of discrete sources. An observation or upper limit placed on such a background brings us new information about the Universe. The project will have an impact on the educational environment at Loyola University New Orleans, a primarily undergraduate institution in Louisiana. This project will maintain a vibrant research activity at Loyola, while incorporating undergraduate students as research assistants.