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Chirp generation for test mass signals

The routines provided in this package were designed to resemble as closely as possible the chirp generating routines for post-Newtonian signals. However, because of the different functional forms for the two types of waveforms some differences where unavoidable.

The main routine is testmass_chirp() which returns $h_+$ and $h_\times$ in a given frequency interval. However, before being able to use testmass_chirp(), one has to read in the data files, calculate the phase $\Phi(v_0,v)$, etc. There are a number of routines provided that allow one to perform these tasks with a minimum of amount of work.

For testmass_chirp() to work, the program must make sure that the two data files containing the mode amplitudes $A_{lm}(v)$ and the luminosity $P(v)$ have been read. It then has to calculate $V(t)$ (which can be inverted to give $t(V)$) and $\Phi(v_0,v)$. Furthermore, it has to make the number of data points known to the package, in order for the interpolation routines to work. The package currently assumes that all data files have the same number of points and that $v$ is equally spaced. Note that all the functions in the package take the orbital frequency $f= \nicefrac{v^3 c^3}{G M \pi}$, instead of $v$, as input.


next up previous contents
Next: Function: testmass_chirp() Up: GRASP Routines: Waveforms from Previous: A note on the   Contents
Bruce Allen 2000-11-19