paired 1.5: binary star candidates from Gaia DR3 radial velocities

paired flags binary-star candidates among the 30,545,303 Gaia DR3 stars with radial-velocity measurements. Most binaries in Gaia are unresolved, but a companion tugs its host, and that motion appears as extra scatter in the star's radial velocities. paired compares each star's RV scatter to what a genuinely single star of the same color and brightness shows; stars with significantly more scatter are binary candidates.

paired 1.5 supersedes the published version 1 (Chance & Ballard 2025, ApJ 992, 131). The significance values are now empirically calibrated against roughly 830,000 stars independently confirmed single by repeat spectroscopy: a cut at p_cal < 0.005 admits a measured 0.5% of true single stars, uniformly across color, brightness, and Gaia visit count. Version 1.5 also adds a second, identically calibrated detection channel (p_width) for the faint regime beyond GRVS = 12, where Gaia stacks visits into one spectrum and orbital motion smears the spectral lines instead of scattering the velocities.

The catalog ships in HDF5 and parquet (identical content, one row per star), with full column and usage documentation. 96.5% of rows carry a calibrated significance value; the remainder carry a status code explaining why not. See HOW_TO_USE.md for recommended cuts and caveats.

Looking forward to the release of DR4 in December 2026, DR4's epoch radial velocities will let bright, well-sampled stars be fit for orbits directly rather than flagged by excess scatter. The calibrated statistic still applies where epochs are sparse or faint, and the calibration approach transfers straight to an epoch-RV statistic in DR4 - expect an update following the release.