Wide bandwidth dual acoustic gravitational wave detectors

In a “dual” detector a wideband sensitivity is obtained by measuring the differential displacement, driven by the gw wave, of the facing surfaces of two nested massive bodies mechanically resonating at different frequencies. By the use of the recently proposed “selective readout” scheme, capable of specifically selecting the signal contributed by the vibrational modes sensitive to the gravitational waves, a flat spectral strain sensitivity could be obtained. In the case of a 3 m diameter Silicon Carbide dual cylinder, the sensitivity expected at the standard quantum limit is better than 10−23 Hz−1/2 in the wide frequency interval 1-4 kHz.