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Function: tau_of_mass()

0 void tau_of_mass(double m1, double m2, double pf, double *tau0, double *tau1)
This function calculates the coordinates $(\tau_0,\tau_1)$ associated with particular values of the masses of the objects in the binary system, and a particular value of frequency $f_0$.

The arguments are:

m1: Input. The first mass (in solar masses).
m2: Input. The second mass (in solar masses).
pf: Input. The value $\pi f_0$. Here $f_0$ is the frequency used in defining the $\tau$ coordinates (see below). It is often chosen to be at (or below) the frequency at which the chirp first enters the bandpass of the gravitational wave detector.
tau0: Output. Pointer to $\tau_0$ (in seconds).
tau1: Output. Pointer to $\tau_1$ (in seconds).

Although one can think of $\tau_0$ and $\tau_1$ as coordinates in the parameter space defined by ([*]) and ([*]) they have simple physical meanings. $\tau_0$ is the time to coalescence of the binary system, measured from the time that the waveform passes through frequency $f_0$, in the zeroth post-Newtonian approximation. $\tau_1$ is the first-order post-Newtonian correction to this quantity, so that to this order the time to coalescence is $\tau_0+\tau_1$.

Author: Bruce Allen, ballen@dirac.phys.uwm.edu
Comments: None.


next up previous contents
Next: Function: m_and_eta() Up: GRASP Routines: Template Bank Previous: Structure: struct Scope   Contents
Bruce Allen 2000-11-19