Post-ISCO Ringdown Amplitudes in Extreme Mass Ratio Inspiral
by Hadar, Shahar and Kol, Barak
17 pages, 2 figures. v3: minor changes
An extreme mass ratio inspiral consists of two parts: adiabatic inspiral and plunge. The plunge trajectory from the innermost stable circular orbit (ISCO) is special (somewhat independent of initial conditions). We write an expression for its solution in closed-form and for the emitted waveform. In particular we extract an expression for the associated black-hole ringdown amplitudes, which reduces to solving certain ordinary (radial) differential equations in the Schwarzschild background.