An RUI Proposal to Investigate Thermal Noise and Higher-Order Statistical Noise in Initial and Advanced LIGO

本课题的研究重点是了解和降低中、高级LIGO的热噪声和上转换噪声。这些噪声源是LIGO中心频率40 - 400hz范围内的限制性噪声源。因此，它们的减少对LIGO的灵敏度和预期事件率有直接的积极影响。PI将探索熔融二氧化硅损耗的基本限制以及高级LIGO光学所需的实际可实现的损耗限制。他将研究新的方法和材料，以减少先进LIGO反射镜涂层的损耗。他将探索改进中间LIGO的悬挂方法，看看一个适度的改变是否能及时提高LIGO的灵敏度。他还将开始设计第三代引力波天文台的测试质量反射镜配置。最后，他将继续开发双相干监测器，为检测上转换噪声提供一种手段，上转换噪声已成为初始LIGO中越来越重要的噪声源。LIGO的成功取决于它是否有能力将灵敏度提高到足以探测到引力波的程度，并以一个真正的天文台所能达到的速度进行探测。实现这一目标的最直接途径是减少LIGO最敏感的中心频率区域的限制性噪声源。PI的研究正是针对这个目标。此外，PI的工作是在一所小型文理学院进行的，这使得本科生甚至高中生都可以参与这项研究。此外，PI还在公共教育和国际合作方面作出了重大努力。他每年做几次公开演讲；他组织了LIGO和Virgo合作项目的首次联合技术会议；他是美国物理学会引力专题小组执行委员会的成员。

This research project focuses on understanding and reducing thermal noise and upconversion noise in Intermediate and Advanced LIGO. These noise sources are the limiting ones in LIGO's central frequency range of 40 - 400 Hz. Thus their reduction has a direct positive impact on LIGO's sensitivity and expected event rate. The PI will explore the fundamental limits to the loss in fused silica and the practically achievable loss limits required for the Advanced LIGO optics. He will investigate new methods and materials for reducing the loss in the mirror coatings for Advanced LIGO. He will explore improved suspension methods for Intermediate LIGO, to see if a modest change may improve LIGO's sensitivity in time for Science Run 6. He will also begin design studies for test mass mirror configuration for third generation gravity wave observatories. Finally he will continue development of a bicoherence monitor to provide a means for detecting upconversion noise, which has become an increasingly important noise source in Initial LIGO.LIGO's success is dependent upon its ability to increase its sensitivity sufficiently to detect gravity waves and to do so at a rate worthy of a true astronomical observatory. The most direct path toward that goal is to reduce the limiting noise sources in LIGO's most sensitive central frequency region. The PI's research is directed precisely at that goal. In addition, the PI's work is conducted at a small liberal arts college, which has allowed undergraduate and even high school students to get involved in this research. In addition the PI also commits significant efforts to public education and international cooperation. He gives a few public lectures each year; he organized the first joint technical meeting between the LIGO and Virgo collaborations; and he serves on the Executive Committee of the American Physical Society's Topical Group on Gravitation.