Gaia Data Release 3: The first Gaia catalogue of eclipsing-binary candidates

Context. Gaia Data Release 3 (DR3) provides a number of new data products that complement the early DR3 made available two years ago. Among these is the first Gaia catalogue of eclipsing-binary candidates containing 2 184 477 sources with brightnesses from a few magnitudes to 20 mag in the Gaia G-band and covering the full sky. Aims. We present the catalogue, describe its content, provide tips for its use, estimate its quality, and show illustrative samples. Methods. Candidate selection is based on the results of variable object classification performed within the Gaia Data Processing and Analysis Consortium. Candidates are then further filtered using eclipsing-binary-tailored criteria based on the G-band light curves. To find the orbital period, a large ensemble of trial periods is first acquired using three distinct period-search methods applied to the cleaned G light curve of each source. The G light curve is then modelled with up to two Gaussians and a cosine for each trial period. The best combination of orbital period and geometric model is finally selected using Bayesian model comparison based on the BIC. A global ranking metric is provided to rank the quality of the chosen model between sources. The catalogue is restricted to orbital periods larger than 0.2 days. Results. Of ∼600 000 available crossmatches, about 530 000 of the candidates are classified as eclipsing binaries in the literature as well, and 93% of them have published periods compatible with the Gaia periods. Catalogue completeness is estimated to be between 25% and 50%, depending on the sky region, relative to the OGLE4 catalogues of eclipsing binaries towards the Galactic Bulge and the Magellanic Clouds. The analysis of an illustrative sample of ∼400 000 candidates with significant parallaxes shows properties in the observational Hertzsprung-Russell diagram as expected for eclipsing binaries. The subsequent analysis of a subsample of detached bright candidates provides further hints for the exploitation of the catalogue. We also address the observed lack of short-period (less than a day) systems in the Magellanic Cloud in comparison to Galactic systems. The orbital periods, light-curve model parameters, and global rankings are all published in the catalogue with their related uncertainties where applicable. Conclusions. This Gaia DR3 catalogue of eclipsing-binary candidates constitutes the largest catalogue to date in terms of number of sources, sky coverage, and magnitude range.