Daniele PE

Precessing binary black holes produce a complicated waveform, reflecting their time-dependent spins and the line of sight. As discussed below in ``Reliable parameter estimation with SpinTaylorF2” , particularly at high mass ratio the precession of two spinning black holes can be reasonably approximated as if the smaller body had no spin. To the extent this approximation holds, then, GW observatories would have no access to the smaller spin, and hence to unique strong-field effects associated with spin-spin interactions.

In a study led by Daniele Trifiro (Pisa), my collaborators and I demonstrate that if suitable sources occur, advanced LIGO can directly and robustly identify effects from both black hole spins in BH-BH binaries. These effects are not subtle; can be identified over a broad range of astrophysically plausible signal amplitudes and source orientations; and include the signature of conserved constants that reflect properties at compact binary birth.

For experts Using sources known to lie on one or the other post-Newtonian resonance, we construct posterior parameter distributions, each point in which can be classified as belonging to one of three classes. These classes are reliably measured.
More broadly, as implied by our prior work, observationally-accessible properties of the nonlinear dynamics at merger encode conserved properties reflecting the compact binary’s asymptotic initial conditions.

• Trifiro et al, Distinguishing black-hole spin-orbit resonances by their gravitational wave signatures. II: Full parameter estimation, submitted to PRD

• 2015 April APS Meeting: A presentation on the method