This is a continuation of a collaborative project between Peter F. Michelson of Stanford University and He En.ke of the Institute of Gravitational Physics of Zhongshan University in Guangzhou, China. This project, which began in 1985, is sponsored by NSF and the Chinese State Education Commission. The direct detection of gravitational radiation is still the most important goal of research in gravitational physics and one of the most challenging problems in experimental physics. The detection of gravity waves would not only be of fundamental importance to physics, but would open up an important new astronomical window on the universe. Resonant.mass detectors have been under development at several institutions including Stanford and Zhongshan universities. The Stanford detector has been utilized in coincidence experiments that have set the lowest upper limits to date on the flux of gravitational radiation. Under the cooperative program between the Stanford and Zhongshan groups during the past five years, a coincidence experiment has been conducted, technical information about large.scale cryogenic detectors has been exchanged, and most recently, investigations of advanced antenna materials and vibration isolation techniques at low temperatures have been conducted. In the proposed study, the investigators will continue to develop improved detector technology, principally in the areas of vibration isolation and materials studies, undertake a collaborative effort to repair and upgrade the 4 K detector at Stanford, exchange information about other gravitational physics experiments in which there is mutual interest, and at the earliest opportunity, carry out another coincidence search for gravitational radiation.
