GW150914

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. There is also a technical details page about the data linked below, and feel free to contact us . There are Science Summaries , covering the information below in ordinary language. There is a one page factsheet about GW150914 , summarizing the event. There are lots of data files available in the sections below, look for the word DATA . Click on each thumbnail image for larger image. See the papers linked below for full information, references, and meaning. Many of the data files linked below have heterogeneous formatting; if you have any questions, please contact us . For full details see LIGO DCC , arXiv , or Phys. Rev. Letters See also the paper "Binary Black Hole Mergers in the First Advanced LIGO Observing Run", LIGO DCC , arXiv , or Phys. Rev. X . The Estimated source parameters below have been updated to come from this latter paper. These papers and all the companion papers can also be found at the LIGO-Virgo-KAGRA Publications page. Note: The numerical relativity waveform that was subtracted to make these figures is consistent with the parameter ranges inferred for GW150914, as noted in the figure caption, but was not tuned to precisely remove the signal. A bit of residual signal, with amplitude smaller than the visible noise, remains in each of these 'Residual' plots. FIG. 1. The gravitational-wave event GW150914 observed by the LIGO Hanford (H1, left column panels) and Livingston (L1, right column panels) detectors. Times are shown relative to September 14, 2015 at 09:50:45 UTC. For visualization, all time series are filtered with a 35-350 Hz band-pass filter to suppress large fluctuations outside the detectors' most sensitive frequency band, and band-reject filters to remove the strong instrumental spectral lines seen in the Fig. 3 spectra. FIG. 2. Left: Estimated gravitational-wave strain amplitude from GW150914 projected onto H1. This shows the full bandwidth of the waveforms, without the filtering used for Fig. 1. Right: The Keplerian effective black hole separation in units of Schwarzschild radii and the effective relative velocity. FIG.3. The average measured strain-equivalent noise, or sensitivity, of the Advanced LIGO detectors during the time analyzed to determine the significance of GW150914 (Sept 12 - Oct 20, 2015). Hanford (H1) is shown in red, Livingston (L1) in blue. The solid traces represent the median sensitivity and the shaded regions indicate the 5th and 95th percentile over the analysis period. The narrowband features in the spectra are due to known mechanical resonances, mains power harmonics, and injected signals used for calibration. Data usage notes: Please Read This First! The data are provided in three formats. HDF5 , Frame (.gwf) , and gzipped ascii text. Many data analysis environments can read in data from HDF5 files, including Python (see the h5py package), MATLAB, C/C++, and IDL. 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 . Technical details especially about data quality and injections Tutorials to work with the strain data . 32 secondsapprox 1 Mbyte DATA hdf5 DATA gwf DATA txt.gz DATA hdf5 DATA gwf DATA txt.gz 4096 secondsapprox 134 Mbyte DATA hdf5 DATA gwf DATA txt.gz DATA hdf5 DATA gwf DATA txt.gz 32 secondsapprox 4 Mbyte DATA hdf5 DATA gwf DATA txt.gz DATA hdf5 DATA gwf DATA txt.gz 4096 secondsapprox 536 Mbyte DATA hdf5 DATA gwf DATA txt.gz DATA hdf5 DATA gwf DATA txt.gz The numerical relativity waveform used in this tutorial can be obtained as a plain-tex