The SB9 catalogue: status, comparison with non-single stars from Gaia DR3 and evolution to SBX

TL;DR

This paper updates and compares the SB9 spectroscopic binary catalog with Gaia DR3 data, analyzing their properties, overlaps, and limitations, and introduces the new SBX catalogue with improved features for stellar research.

Contribution

It provides the latest SB9 catalog update, performs a detailed cross-match with Gaia DR3, and launches SBX with enhanced data access and usability for the astronomical community.

Findings

SB9 contains 4003 systems, including higher-order multiples.

Approximately 20-30% overlap with Gaia NSS, limited by selection criteria.

SBX offers improved data quality, accessibility, and integration with Virtual Observatory standards.

Abstract

The Ninth Catalogue of Spectroscopic Binary Orbits (SB9) is a comprehensive compilation of spectroscopic binaries (SBs) with orbital parameters sourced from literature, comprising approximately 4000 systems (2800 single-lined and 1200 double-lined). This work presents the latest status of SB9 after two decades of development, detailing the statistical properties of SBs through orbital period distributions and eccentricity-period diagrams categorized by spectral type and evolutionary stage. We performed a rigorous cross-match with Gaia Data Release 3 (DR3) to update astrometric parameters and compare SB9 with the Gaia DR3 Non-Single Star (NSS) catalogue. Our methodology utilized positional separations, magnitudes, and proper-motion back-propagation for identification. The final SB9 version updated by D. Pourbaix includes 4003 systems, including higher-order multiples: 152 triples, 71 quadruples, and 14 higher-order systems. Of these, 3976 have Gaia DR3 identifiers; 21 are too bright and six too faint for detection. Ten SB9 systems with periods exceeding 1180 days were spatially resolved by Gaia DR3. We identified a common sample of 827 binaries cross-matched with Gaia NSS, with 655 considered highly reliable based on period and eccentricity differences under 10%. The limited overlap (20-30% of SB9) results from NSS selection cuts, brightness limits, and temporal baselines. This study highlights the complementary strengths of both catalogues and establishes a benchmark sample for binary star research. Finally, this work marks the transition of SB9 into SBX (The eXtended Catalogue of Spectroscopic Binary Orbits), featuring a modern relational database, improved web interface, and Virtual Observatory access standards to enhance data quality and accessibility for the stellar community.