Note: Virgo joined the O2 observing run on August 1st, 2017. At the time of the event the Advanced Virgo detector was in a commissioning phase in preparation for the O2 science run. The detector was operating with limited sensitivity. No fully characterized strain data from Virgo is available for this event
After data collection, several independently-measured terrestrial contributions to the detector noise were subtracted
from the LIGO data using Wiener filtering. This subtraction removed calibration
lines and 60 Hz AC power mains harmonics from both LIGO data streams. At times near GW170608, the sensitivity of LIGO-Hanford
was particularly improved by the subtraction of laser pointing noise; several broad peaks in the 150 - 800 Hz
region were effectively removed, increasing the Binary Neutron Star horizon distance of that detector by typically 25%.
† The ± 10 msec window for peak amplitude is due to different arrival time in each of the LIGO detectors.
Strain data before noise subtraction
These files contain data before noise subtraction. These data were produced in low-latency, and used by the search pipelines to evaluate event significance.
Below are links to strain h(t) time series centered at GPS 1180922494.
The last 7 seconds of the H1 4096 second long files in the tables below contain NaN in the place of strain values due to the detector not being in a nominal locked state for data analysis.
The H1 data has excess noise at frequencies below 30 Hz due to routine instrumental activity to minimize angular control couplings. Users should restrict analysis to frequencies above 20 Hz for L1 and should restrict analysis for H1 to frequences above 30 Hz.
The files and some technical notes may all be found in LIGO P1700413
md5 checksums may be used to ensure files are correctly downloaded.
Strain Data at 4096 Hz
Strain h(t) time series centered at GPS 1180922494,
32 seconds (event signal reaches peak amplitude 16.49 seconds ± 10 msec from start†)