SGER -- Measuring Charging Effects on LIGO Optics

Trinity University, San Antonio TX

Investigators

Abstract

This award supports a research program to measure charge buildup and correlation time in vacuum for LIGO-like optics, as well as a variety of materials, coatings preparations, and environmental factors. The method to be used for measuring surface charge is a Kelvin probe, which creates a capacitance between probe and sample and then modulates this capacitance to generate an AC signal proportional to the sample charge level. The work will be performed at Trinity University by the PI and an undergraduate. The proposed research is of urgent importance to Initial LIGO and any enhancements following the current science run, due to the recent observation of a disappearing noise source in the 40-100 Hz frequency band at the LIGO Livingston Observatory which may be connected to the discharging of an optic. The research is also necessary for Advanced LIGO and third generation interferometers in order to reduce noise in their most sensitive frequency range.