Range check task

This task is designed to provide the information of inspiral range and the sensitivity of the interferometer around the triggered time.

Requirements

This task requires the following packages that may not be included in the requirements list for dqrtasks:

  • gwpy

  • gwdetchar

Description

This task will provide the information of inspiral range of the interferometer around the triggered time. In default, the task will monitor the 512 seconds data before the trigger time.

The task performs following steps:

  1. Find the locked segment just before the triggered time (duration is selected by window variable, in the example bloe, 500 s), and resample the data. Due to reampleing, we can reduce the computational costs. In the example, we use the resample frequency of 4096 Hz, similar to standard CBC search.

2. Evaluate the time series of inspiral range for several combination of CBC events(1.4-1.4, 10-10, 30-30Msun). Compute the average value of inspiral range (shown in the table). These will be done by range_timeseries in gwpy package. The maximum frequency for the inspiral range is properly computed in the function, depending on the component mass.

  1. Evaluate the PSD from same data for complementary information. To see the stability of sensitivity, the task uses two kinds of data with different durations such as 512 seconds and 8 seconds before the trigger time. Note that the fftlength is same as step 2, such as 4 seconds.

The task will not provide p-value. This is an informative task.

Example command-line

This is the help message:

$ dqr-rangecheck --help
usage: dqr-rangecheck [-h] [-t TAG] [-v] [--output-dir OUTPUT_DIR]
                      [--channel CHANNEL] [--frame-type FRAME_TYPE]
                      [--science-flag SCIENCE_FLAG]
                      [--long-seg-len LONG_SEG_LEN]
                      [--short-seg-len SHORT_SEG_LEN] [--fft-len FFT_LEN]
                      [--overlap OVERLAP] [--psd-var-stride PSD_VAR_STRIDE]
                      [--psd-method PSD_METHOD] [--psd-window PSD_WINDOW]
                      [--f-low F_LOW] [--f-high F_HIGH]
                      [--resample_rate RESAMPLE_RATE] [--window WINDOW]
                      [--padding PADDING] [--chunk_range CHUNK_RANGE]
                      gps

DQR task that checks the inspiral range of the data

positional arguments:
  gps

optional arguments:
  -h, --help            show this help message and exit
  -t TAG, --tag TAG
  -v, --verbose
  --output-dir OUTPUT_DIR
  --channel CHANNEL
  --frame-type FRAME_TYPE
  --science-flag SCIENCE_FLAG
  --long-seg-len LONG_SEG_LEN
  --short-seg-len SHORT_SEG_LEN
  --fft-len FFT_LEN
  --overlap OVERLAP
  --psd-var-stride PSD_VAR_STRIDE
  --psd-method PSD_METHOD
  --psd-window PSD_WINDOW
  --f-low F_LOW
  --f-high F_HIGH
  --resample_rate RESAMPLE_RATE
  --window WINDOW
  --padding PADDING
  --chunk_range CHUNK_RANGE

Example config

[rangecheck]
description = range check
librarian = derek.davis@ligo.org
include_in_dag = True
tier = 1
question = Is there a high significance that a glitch was present overlapping the candidate based on strain info?
executable = dqr-rangecheck
request_memory = 400MB
arguments = "${t_0} -v --output-dir ${outdir}   --channel L1:DCH-CLEAN_STRAIN_C02   --frame-type L1_CLEANED_HOFT_C02   --long-seg-len 512   --short-seg-len 8   --fft-len 4   --overlap 2   --psd-var-stride 0.1   --psd-method median   --psd-window hann  --resample_rate 4096   --window 500   --padding 4  --f-low 10   --f-high 1000"

Example results page

An example page for GW170817 can be found here.