IAS-O3a Catalog

Authors

Seth Olsen, Tejaswi Venumadhav, Jonathan Mushkin, Javier Roulet, Barak Zackay and Matias Zaldarriaga.

About

The IAS-O3a catalog contains binary black hole candidates found with the IAS search pipeline in the public data from the first half of the third observing run of advanced LIGO and advanced Virgo (O3a), that have probability of astrophysical origin greater than 0.5. This includes 42 events, of which 10 were first reported there.

The IAS-O3a search was restricted to times in which data from both the LIGO-Hanford and LIGO-Livingston detectors were available. Data from the Virgo detector were not used in the computation of significance, but were used in parameter estimation when available.

The pipeline used for this O3a search is largely based on the IAS pipeline developed and used for searches of the O1 and O2 runs. The template bank was constructed with geometric placement as described in PhysRevD.99.123022. False-alarm rates are computed within each template bank; the search used 6 independent template banks.

Strain Data

Strain data was obtained from the Gravitational Wave Open Science Center, with additional cleaning and PSD estimation using the signal processing methods developed in PhysRevD.104.063034.

Parameter Estimation

Events were analyzed under two different priors, along with comoving and non-comoving VT for each, (here referred to as "IAS" and "LVK"). These only differ in the spin distribution (the IAS prior is uniform in effective spin, the LVK prior is uniform in spin magnitudes and isotropic in spin orientations). In both cases, the prior for the masses is uniform in detector-frame component masses and uniform in comoving volume-time. Parameter inference were done with the software cogwheel, described in PhysRevD.106.123015 and open source cogwheel software in github.

(Note: this description applies to the parameter estimation results displayed in GWOSC and hosted on Zenodo. The search data products in GitHub also include parameter estimations, but only for the set of 10 events that were new to the IAS-O3a catalog.)

Related Products

  • IAS-O3a catalog paper: arXiv, PRD
  • IAS-O3a search data products: GitHub
  • Parameter estimation samples: Zenodo

Event Portal links of 10 new IAS-O3a BBH mergers which were not recorded in GWTC:

Event Portal link containing full list of IAS-O3a events

GWOSC Background Information:


The DOI for this catalog is 10.5281/zenodo.14367768.

Release Notes

  • IAS-O3a events released: June 21, 2023
  • Revised this documentation: Jan 30th, 2025
  • Updated Zenodo link: Feb 12th, 2025
  • Released: May 5th, 2025