Overview and stellar statistics of the expected Gaia Catalogue using the Gaia Object Generator

TL;DR

This paper presents a simulated Gaia Catalogue with observational errors, analyzing its potential for astrometric, photometric, and spectroscopic data to understand Gaia's expected scientific yield.

Contribution

It introduces a detailed simulation of the Gaia Catalogue including observational errors, providing comprehensive statistics on data quality and expected measurement uncertainties.

Findings

Simulated catalogue contains 523 million stars with detailed error estimates.

Analysis shows the potential accuracy of Gaia's astrometric and photometric measurements.

Provides insights into the impact of observational errors on Gaia data analysis.

Abstract

Aims: An effort has been undertaken to simulate the expected Gaia Catalogue, including the effect of observational errors. A statistical analysis of this simulated Gaia data is performed in order to better understand what can be obtained from the Gaia astrometric mission. This catalogue is used in order to investigate the potential yield in astrometric, photometric and spectroscopic information, and the extent and effect of observational errors on the true Gaia Catalogue. This article is a follow-up to Robin et. al. (2012), where the expected Gaia Catalogue content was reviewed but without the simulation of observational errors. Methods: The Gaia Object Generator (GOG) catalogue is analysed using the Gaia Analysis Tool (GAT), producing a number of statistics on the catalogue. Results: A simulated catalogue of one billion objects is presented, with detailed information on the 523 million individual single stars it contains. Detailed information is provided for the expected errors in parallax, position, proper motion, radial velocity, photometry in the four Gaia bands, and physical parameter determination including temperature, metallicity and line of sight extinction.