Very high Q measurements on a fused silica monolithic pendulum for use in enhanced gravity wave detectors

The results of a very high Q factor measurements for a 2.8 kg fused silica mass suspended by two fused quartz fibers attached by a novel technique for joining fused silica or quartz are presented. This is the heaviest test mass to date to be hung on fused quartz and tested in this way. Results are very encouraging even if not at the theoretical limit that one expects from the inherent material losses of fused quartz.