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Function: LS_waveform()

void LS_waveform(float h[], struct LS_physical_constants phys_const, float sky_theta, float sky_phi, float polarization, float dt, int n_samples)
This function calculates the stress as measured by a LIGO like detector due to a hung-up collapsing core. It uses the routines LS_phas_and_freq to obtain the wave phase and reduced frequency at regular time intervals, calculates $h_+$ and $h_\times$ at each interval according to ([*]), and then converts these into a single detector stress at each interval using beam pattern factors calculated with beam_pattern. Note that the external variable A is assigned a value here for use in LS_freq_deriv (see [*]).

The arguments are:

h[]: Output. An array which holds the detector stress due the gravitational wave of the hung-up core at equally spaced time intervals. h[] must be allocated sufficient memory before being passed to LS_waveform().
phys_const: Input. A structure of type LS_physical_constants (see subsection [*]) which contains the physical parameters of the hung-up core.
sky_theta: Input. The polar angle from zenith in radians.
sky_phi: Input. The azimuthal angle (measured counter clockwise from first arm) in radians.
polarization: Input. The polarization angle in radians.
dt: Input. The time interval (in seconds) at which the detector stress values should be output.
n_samples: Input. The number of detector stress values to be output (i.e. the number of elements in the array h[]).

Authors: Warren G. Anderson, warren@ricci.phys.uwm.edu and Patrick Brady, patrick@tapir.caltech.edu
Comments: This function currently calculates the stress at a user defined distance from the hung-up core. For realistic distances, this leads to small values (of the order of 10e-22 at 10 MPc). If one wishes to have numbers of the order of unity, simply set the distance in the structure phys_const to be 10e-22.


next up previous contents
Next: Example: LS_filter program Up: GRASP Routines: Supernovae and Previous: Function: LS_phas_and_freq()   Contents
Bruce Allen 2000-11-19