SUPERCONDUCTOR REENTRANT CAVITIES FOR THE PARAMETRIC TRANSDUCERS OF THE BRAZILIAN MARIO SCHENBERG GRAVITATIONAL WAVE DETECTOR

摘要

Parametric transducers used in gravitational wave detectors convert mechanical vibrations into electrical signals at much higher frequency, amplifying the signal energy by the intrinsic parametric gain. One kind of parametric transducer, which will be used in the Brazilian Mario Schenberg detector [1], was developed by both the Japanese and the Australian groups [2],[3]. This transducer consists of a reentrant superconducting niobium cavity having a central post with a narrow gap between its top and an oscillating end wall, mechanically coupled to the gravitational wave antenna at its resonant frequency.