Investigating the Low-Mass Black Hole Population in a Milky Way-like Galaxy Using COSMIC-SSE

The low-mass gap between the heaviest neutron stars and the lightest black holes remains a significant puzzle in astrophysics. This research uses COSMIC, a Python package based on Binary Star Evolution (BSE), to simulate black hole (BH) and detached luminous companion (LC) binaries within a Milky Way-like galaxy. Initial conditions are derived from FIRE simulations, and systems are evolved using COSMIC-SSE with two supernova prescriptions: RAPID and DELAYED. The goal is to predict the properties and distributions of low-mass black holes potentially observable in Gaia DR4. The study explores key questions about the mass distribution of low-mass black holes, the impact of binary properties on observability, and the underlying formation mechanisms. The results indicate no observable BH-LC systems in Gaia DR4, offering insights into both the low-mass gap problem and the limitations of current observational data.