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(ed.). Gravitational waves (IOP, 2001)(422s).

(ed.). Gravitational waves (IOP, 2001)(422s).

(ed.). Gravitational waves (IOP, 2001)(422s).

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Taking the scalar product we find<strong>Gravitational</strong> wave radiation in the JBD theory 159c 0,0 (t) = 4π 3 S0,0 ijE ij (t)c 2,m (t) = 8π15 S2,m ijE ij (t) (11.27)and then for the NP parameters√ √51 22 =16π c 2,0(t) −4π c 0,0(t), 2 =− 1 √512 π c 2,0(t) − 1√112 π c 0,0(t)√ √1515Re 4 =−32π [c 2,2 + c 2,−2 ], Im 4 =−i32π [c 2,2 − c 2,−2 ]Re 3 = 1√1516 π [c 2,1 − c 2,−1 ], Im 3 = i√1516 π [c 2,1 + c 2,−1 ]. (11.28)Equations (11.28) relate the measurable quantities c l,m with the GW polarizationstates, describ<strong>ed</strong> by the NP parameters. Equations (11.28) can be put incorrespondence with the output of experimental measurements if c l,m aresubstitut<strong>ed</strong> with their Fourier components at the quadrupole and monopoleresonant frequencies which, for the sake of simplicity, we collectively denote byω 0 . c l,m (ω 0 ) can be determin<strong>ed</strong> in the following way: once the Fourier amplitudesA N (ω 0 ) are measur<strong>ed</strong>, by Fourier transforming (11.14) and (11.15) we get theRiemann amplitudes E ij (ω 0 ) which, using (11.27), yield the desir<strong>ed</strong> result.In order to determine the A N (ω 0 ) amplitudes from a given GW signal thefollowing two conditions must be fulfill<strong>ed</strong>:• the vibrational states of the five-fold degenerate quadrupole and monopolemodes must be determin<strong>ed</strong>. The quadrupole modes can be studi<strong>ed</strong> byproperly combining the outputs of a set of at least five motion sensorsplac<strong>ed</strong> in independent positions on the sphere surface. Explicit formulas forpractical and elegant configurations of the motion sensors have been report<strong>ed</strong>by various authors [15, 16]. The vibrational state of the monopole modeis provid<strong>ed</strong> directly by the output of any of the above-mention<strong>ed</strong> motionsensors. If resonant motion sensors are us<strong>ed</strong>, since the quadrupole andmonopole states resonate at different frequencies, a sixth sensor is ne<strong>ed</strong><strong>ed</strong>.• The spectrum of the GW signal must be sufficiently broadband to overlapwith the antenna quadrupole and monopole frequencies.11.3 <strong>Gravitational</strong> wave radiation in the JBD theoryIn this section we analyse the signal emitt<strong>ed</strong> by a compact binary system inthe JBD theory. We compute the scalar and tensor components of the powerradiat<strong>ed</strong> by the source and study the scalar waveform. Eventually we considerthe detectability of the scalar component of the radiation by interferometers andresonant-mass detectors.

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