Gravitational Wave Open Science Center

Data release for event GW170104

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 LIGO Livingston observatories.

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.


Estimated Source Parameters

Quantity Value Unit
UTC time 2017-01-04T10:11:58.6
GPS time 1167559936.6
Primary mass 31.2 +8.4 -6.0 Msun
Secondary mass 19.4 +5.3 -5.9 Msun
Chirp mass 21.1 +2.4 -2.7 Msun
Total mass 50.7 +5.9 -5.0 Msun
Final mass 48.7 +5.7 -4.6 Msun
Radiated energy 2.0 +0.6 -0.7 Msun c^2
Peak luminosity 3.1 +0.7 -1.3 10^56 erg s^-1
Effective inspiral spin -0.12 +0.21 -0.30
Final spin 0.64 +0.09 -0.20
Luminosity distance 880 +450 -390 Mpc
Source redshift 0.18 +0.08 -0.07
False alarm rate < 1.4e-05 yr^-1
Signal to Noise Ratio 13
Sky localization 1200 deg^2

The data from the observatories from which the science is derived:

Gravitational-Wave Strain Data

Strain Data at 4096 Hz

Strain h(t) time series centered at GPS 1167559936.

Hanford Livingston
32 seconds (event is 16.60 seconds from start) hdf5 gwf txt.gz hdf5 gwf txt.gz
4096 seconds (event is 2048.60 seconds from start) hdf5 gwf txt.gz hdf5 gwf txt.gz

Strain Data at 16384 Hz

Strain h(t) time series centered at GPS 1167559936.

Hanford Livingston
32 seconds (event is 16.60 seconds from start) hdf5 gwf txt.gz hdf5 gwf txt.gz
4096 seconds (event is 2048.60 seconds from start) hdf5 gwf txt.gz hdf5 gwf txt.gz

Sky Localization

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.

Visualize the source sky localization estimated from LIGO and Virgo observations.

Low-latency (rapid) skymap from BAYESTAR:

Refined skymap from LALInference:

A python library for reading the FITS DATA is healpy. A very simple healpy code to work with LIGO-Virgo skymaps is here. A large number of simulated skymaps is available here and here.


About the Instruments and Collaborations

See the instruments and collaborations page.


There is a technical details page about the data linked above, and feel free to contact us.

Revision History