A resonant mass detector is characterized by those eigenmodes having the appropriate

1. A resonant mass detector is characterized by those eigenmodes having the appropriate (quadrupole) symmetry cylindrical bar only one quadrupole mode interacts strongly with GWs The cross section is dependent on the wave propagation direction. The single output is a (unknown) combination of the components (same for an interferometer) sphere five degenerate quadrupole modes (described using the basis of the five spherical harmonics Y2m with m=±2,±1,0; the same basis can be used to express hij in the equivalent spherical components hm) The cross section is omnidirectional The five outputs determine the five parameters: h+ hx H hs Xylophone in its own (all spheroidal modes have high cross section)

2. Spherical detectors • Transducer arrangement and deconvolution technique • Study of the coupling of resonant transducers with the sphere modes • on a realistic scale (miniGrail) • Fast cooling (miniGrail) • Study of the effect of cosmic rays at the Dafne Beam Test Facility (RAP) • Determination of the welding technique • Optimization of read-out • Study of the observatory capability

3. GOAL: Large Spherical Detector • Detecting collapses and • chirps @ 200Mpc • Determining • Source direction • Chirp mass • A chirp signal excites the two • modes at different times. • This double passage technique • determines the chirp mass. •  • gw~ 10-9

4. D = 4.8 m; f1=300 Hz; f2=1000 Hz; SQL Collapses and chirps @ 200Mpc gw~ 10-9 • HOLLOW SPHERES • Can be realized in large dimensions - 4 to 6 meters diameter • 200-300 Hz frequency • Ideal detector for coincidences and stochastic background searches with the advanced interferometer • Xylophone in its own (all spheroidal modes have high cross section) Goal: Large hollow sphere