GWTC-4.0: Parameter estimation data release

This material is part of several data products associated with GWTC-4.0, the fourth Gravitational-Wave Transient Catalog from the LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration. For more information, see the results paper (dcc.ligo.org/LIGO-P2400386/public), the related material linked from this page, and the GWTC-4.0 data release documentation (www.gw-openscience.org/GWTC-4.0/).Parameter estimation data releaseThis data release contains posterior samples (*.hdf5) for gravitational-wave candidates from the first part of the fourth observing run (O4a) as well as a summary file (IGWN-GWTC4p0-0f954158d_720-PESummaryTable.hdf5) that includes a table of credible intervals for all released posterior samples. We provide results for all O4a candidates that have a false alarm rate of less than 1 per year. There is one .hdf5 file per event that contains posterior samples for all parameter estimation runs on that event, as well as mixed samples where multiple waveform models have been equally weighted.In addition to containing the posterior samples, the .hdf5 files also contain metadata about the analyses, including the configuration files (which specify details such as the detector data analysed), noise power spectral densities (potentially for a superset of the detectors used in the analysis), priors, and calibration uncertainty envelopes. See the paper appendices and the provided notebook for further informationThe inference of the source parameters were performed with Bilby. The results are formatted using PESummary.This release is primarily composed of results from the first part of O4 (O4a). A similar release was made for the previous GWTC-3.0 catalog that contained candidates from the second part of O3 (O3b). Sky localization data releaseThe sky localization tar file (IGWN-GWTC4-0f954158d_720-Archived_Skymaps.tar.gz) contains candidate sky localizations corresponding to different parameter estimation configurations (.fits). There is one .fits file per set of posterior samples.Python notebookThe Python notebook (GWTC4p0_PE_data_release.ipynb) explains how to read and use the data files included in this release with a selection of examples.How to download all files from this pageIf you would like to download all files on this page, we recommend zenodo_get:pip install zenodo_getzenodo-get RECORD_ID_OR_DOIwhere the record ID for the most recent version of this page is 16053483 and IDs for other versions can be found in the Versions section at the side of this page.Additional informationFor more general background on gravitational-wave search analysis and sky maps, try the materials from a GW Open Data Workshop or the guide to LIGO–Virgo data analysis.