Gravitational Radiation Detectors at 145 Hz
Abstract
A pair of gravitational radiation detectors at ν0{=}145 Hz have been designed and constructed. The 1400-kg aluminum square antennas, 1.65× 1.65× 0.19 m3 with cuts on each side, have a directivity gain of 4 db. Each antenna is equipped with an electrostatic transducer with coupling constant β∼1.8× 10-3, followed by a low noise FET amplifier. Well isolated from all conceivable terrestrial disturbances, the antennas show the Brownian motion, 18 db over noise within a bandwidth of 1 Hz. After AD conversion with a sampling period of Δ{t}{=}1 sec, the effective noise of the detectors in term of the antenna temperature is Teff{\cong}10K. Correlation of signals from two detectors over observation time NTΔ t will reveal NG short gravitation radiation pulses having energy spectrum density F(ν0)[J m-2 Hz-1], if NG< F(ν0)2>≳5.9×1011NT1/2.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- May 1976
- DOI:
- 10.1143/JJAP.15.833
- Bibcode:
- 1976JaJAP..15..833N
- Keywords:
-
- Antennas;
- Electronic Transducers;
- Gravitational Waves;
- Radiation Measuring Instruments;
- Calibrating;
- Circuit Diagrams;
- Signal Processing;
- Transistor Amplifiers;
- Vibration Isolators;
- Vibration Measurement;
- Instrumentation and Photography