This page has been prepared by the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration to inform the broader community about a
confirmed astrophysical event observed by the gravitational-wave detectors, and to make the data around that time available for others to analyze.
GW170104 was observed at GPS time 1167559936.6 == January 04 2017, 10:11:58.6 UTC. It was recovered with a network signal-to-noise ratio of 13 and a false-alarm-rate of once per 70,000 years.
The event was detected in data from the
LIGO Hanford and
This page serves as a supplement to the paper
GW170104: Observation of a 50-solar-mass binary black hole coalescence at redshift 0.2
which is available from LIGO DCC.
There are more open data about this event, in the files attached to the above paper
in the LIGO DCC.
The md5 checksums provide a check for downloaders that they have received the right file: run the Unix command "md5" (or "md5sum", depending on your OS) on your file and compare to LOSC published values. If different, try downloading again, and if the problem persists, contact us.
The location of GW170104 in the sky can be determined only roughly using the data from the two gravitational-wave detectors. A "skymap", representing the position probability as a function of astronomical sky coordinates (right ascension and declination), was initially computed by a software package called BAYESTAR. After final calibration of the data, the skymap was recomputed with a more sophisticated package called LALInference which simultaneously adjusts all the source parameters and allows for calibration uncertainties.