Unpublished Gaia black hole systems in pre-release data

Ascertain how many black hole binaries present in the pre-release Gaia data set were not publicly reported, in order to enable robust population inference for long-period black hole–star binaries.

Background

Gaia BH3 was released ahead of Gaia DR4, and the paper emphasizes that population inference is sensitive to the number of comparable systems that may exist but were not published in the pre-release data. The explicit unknown here affects conclusions about the occurrence rate and period distribution of detectable black hole binaries.