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Example: ringdown program

This example uses the function qn_ring() to compute the black hole quasinormal ringdown waveform for a preset mode and inclination. The waveform as a function of time is written to standard output in three columns: the time, the plus polarization, and the cross polarization. A Plot of the quasinormal ringdown waveform data is shown in figure [*].

Figure: A plot of the plus and cross polarizations of the gravitational wave strain, at a (unphysical!) distance  $GM_\odot/c^2=T_\odot c\simeq1.4766\,{\mathrm{km}}$, for the fundamental $\ell=m=2$ mode of a black hole with mass $M=50M_\odot$, dimensionless angular momentum parameter $0.98$, and fractional mass loss $\epsilon=0.03$, with inclination and azimuth $\iota=0$ and $\beta=0$. The data was produced by the program ringdown.
\begin{figure}\begin{center}
\index{colorpage}
\epsfig{file=Figures/ring.eps,height=7.5cm}\end{center}\end{figure}

Includes/ringdown.tex

Author: Jolien Creighton, jolien@tapir.caltech.edu



Bruce Allen 2000-11-19