Low Noise Suspensions and Readout Systems for Future LIGO Interferometers

California Institute Of Technology, Pasadena CA

Investigators

Abstract

This proposal requests support for Professor Vladimir Braginsky and his group at the Moscow State University (MSU) in Moscow, Russia. Braginsky and his group are members of the LIGO Scientific Collaboration (LSC) and they propose to continue research on topics of great interest to the LIGO project to which the group has made outstanding contributions over the years. While most of the research will be carried out at MSU, Braginsky and his colleagues will be in frequent close contact with LIGO Laboratory and LSC members as the collaboration works to develop new tools and techniques that will be used in Advanced LIGO detectors. The MSU group will focus their research on the identification and measurement of excess noise in the suspensions and coatings of LIGO's mirror and on searches for new, as yet unknown, nonlinear noise sources with the goal of reducing the noise level that limits the sensitivity of LIGO in its quest to detect gravitational waves. In addition, they will explore theoretical ideas and perform experiments related to breaking through the quantum limit on measurement precision that is expected to be reached by Advanced LIGO. This limit was pointed out by Braginsky a number of years ago, and interest in trying to avoid this limit is now being pursued in a number of laboratories. Schemes for accomplishing this (called "Quantum-Non-Demolition" - a term invented by Braginsky) will be studied by the MSU group, the acknowledged world leaders in this topic.