lalsim-burst

Simulates a generic burst gravitational waveformS.

Synopsis

lalsim-burst [options]

Description

The lalsim-burst utility produces a stream of a simulated gravitational waveform for a generic burst. The output data is the gravitational waveform polarizations in the time domain. The output is written to standard output as a three-column ascii format. The first column gives the time corresponding to each sample and the remaining columns give the gravitational waveform values for the two polarizations.

Options

[default values in brackets]

-h, --help

print a help message and exit

-v, --verbose

verbose output

-w WAVEFM, --waveform=WAVEFM

the waveform to generate

-t DT, --duration=DT

duration (seconds)

-f FREQ, --frequency=FREQ

frequency (Hz)

-b BW, --bandwidth=BW

bandwidth (Hz)

-q Q, --quality-factor=Q

quality factor (dimensionless)

-e ECC, --eccentricity=ECC

eccentricity 0<=ECC<=1 [0]

-p PHI, --phase=PHI

phase (degrees) [0]

-A AMP, --amplitude=AMP

amplitude (dimensionless or \( {\rm s}^{-1/3} \))

-H HRSS, --hrss=HRSS

root-sum-squared amplitude ( \( {\rm Hz}^{-1/2} \))

-F FLUENCE, --fluence=FLUENCE

isotropic energy fluence ( \( M_\odot c^2 / {\rm pc}^2 \))

-R SRATE, –sample-rate=SRATE

sample rate (Hz) [16384]

Waveforms Supported

BLTWNB

band-limited white-noise burst
required parameters: duration, frequency, bandwidth, eccentricity, fluence

StringCusp

cosmic string cusp
required parameters: amplitude, frequency

StringKink

cosmic string kink
required parameters: amplitude, frequency

StringKinkKink

cosmic string kink
required parameters: amplitude

SineGaussian

cosine- or sine-Gaussian
required parameters: quality-factor, frequency, hrss, eccentricity, phase

Gaussian

Gaussian
required parameters: duration, hrss

Impulse

delta-function impulse
required parameters: amplitude

Environment

The LAL_DEBUG_LEVEL can used to control the error and warning reporting of lalsim-burst. Common values are: LAL_DEBUG_LEVEL=0 which suppresses error messages, LAL_DEBUG_LEVEL=1 which prints error messages alone, LAL_DEBUG_LEVEL=3 which prints both error messages and warning messages, and LAL_DEBUG_LEVEL=7 which additionally prints informational messages.

The GSL_RNG_SEED and GSL_RNG_TYPE environment variables can be used to set the random number generator seed and type respectively when generating band-limited white-noise bursts.

Exit Status

The lalsim-burst utility exits 0 on success, and >0 if an error occurs.

Example

The command:

lalsim-burst --waveform BLTWNB --duration 0.1 --frequency 100 --bandwidth 100 --fluence 1e-14

produces a three-column ascii output to standard output; the rows are samples (at the default rate of 16384 Hz), and the three columns are 1. the time of each sample, 2. the plus-polarization strain, and 3. the cross-polarization strain. The waveform produced is a band-limited white-noise burst with equal power in its two polarizations (eccentricity=0, which is the default value), a duration of 0.1 seconds, a frequency of 100 Hz, a bandwidth of 100 Hz, and a fluence of \( 10^{-14}\, M_\odot c^2 / {\rm pc}^2 = 0.01\, M_\odot c^2 / {\rm Mpc}^2 \simeq 1.9\, {\rm J} / {\rm m}^2 \).

The command:

lalsim-burst -w SineGaussian -q 9 -e 1 -p 90 -f 150 -H 1e-22

produces a Q=9 linearly polarized (since the eccentricity is set to 1) sine-Gaussian (not a cosine-Gaussian since the phase is set to 90 degrees) centered at 150 Hz having root-sum-squared strain \( h_{\mathrm{rss}} = 10^{-22}\, {\rm Hz}^{-1/2} \).