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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
associated
with particular values of the masses of the objects in the binary system, and a particular
value of frequency .
The arguments are:

`m1`: Input. The first mass (in solar masses).
`m2`: Input. The second mass (in solar masses).
`pf`: Input. The value . Here is the frequency
used in defining the 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 (in seconds).
`tau1`: Output. Pointer to (in seconds).

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

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

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Bruce Allen
2000-11-19