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

We present fur the first time the results of very high Q factor measurement s for a 2.8 Erg fused silica mass suspended by two fused quartz fibers atta ched by a novel technique for joining fused silica or quartz. The Q for the pendulum mode at 0.93 Hz was (2.3 +/- 0.2) x 10(7), the highest value demo nstrated to date for a mass of this size; By employing such a new suspensio n system the sensitivity of the gravitational wave detectors currently unde r construction can be increased up to 1 order of magnitude.