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Function: LS_phas_and_freq()

void LS_phas_and_freq(double Phi[], float u[], float A, float fmax, float dt, int n_samples)
This function integrates Lai and Shapiro's frequency and phase evolution equations, ([*]) and ([*]), for a hung-up collapsed core. We use numerical recipes odeint, an adaptive step size 4th order Runge-Kutta integrator for the frequency integration and a simple trapezoidal integration for the phase.

The arguments are:

Phi[]: Output. An array which holds the phase of the gravitational wave in radians at equally spaced time intervals. Phi[] must be allocated sufficient memory before being passed to LS_phas_and_freq().
u[]: Output. An array which holds the reduced frequency (frequency divided by $f_{max}$) of the gravitational wave at equally spaced time intervals. u[] must be allocated sufficient memory before being passed to LS_phas_and_freq().
A: Input. The Amplitude $A$ as calculated in ([*])
fmax: Input. The maximum frequency, $f_{max}$. Usually taken from the appropriate field of a
LS_physical_constants structure.
dt: Input. The time interval (in seconds) at which the phase and frequency values should be output.
n_samples: Input. The number of phase and frequency values to be output (i.e. the number of elements in the arrays Phi[] and u[]).

Authors: Warren G. Anderson, warren@ricci.phys.uwm.edu and Patrick Brady, patrick@tapir.caltech.edu


next up previous contents
Next: Function: LS_waveform() Up: GRASP Routines: Supernovae and Previous: Function: LS_freq_deriv()   Contents
Bruce Allen 2000-11-19