LISA capture sources: Approximate waveforms, signal-to-noise ratios, and parameter estimation accuracy

Captures of stellar-mass compact objects (COs) by massive $(\ensuremath{\sim}{10}^{6}{M}_{\ensuremath{\bigodot}})$ black holes (MBHs) are potentially an important source for LISA, the proposed space-based gravitational-wave (GW) detector. The orbits of the inspiraling COs are highly complicated; they can remain rather eccentric up until the final plunge, and display extreme versions of relativistic perihelion precession and Lense-Thirring precession of the orbital plane. The amplitudes of the strongest GW signals are expected to be roughly an order of magnitude smaller than LISA's instrumental noise, but in principle (i.e., with sufficient computing power) the GW signals can be disentangled from the noise by…