Develop self-consistent modeling of evolved binary populations

Develop a self-consistent binary-population model that samples coeval binary systems with metallicity-dependent evolution, correctly accounts for stellar masses that survive to the ages of ultra-faint dwarf-galaxy populations, and eliminates the unphysical high-mass companion tail in forward-modeled radial-velocity observations.

Background

The Binary Observation Simulator currently assigns binary orbital properties using prescribed distributions and pairs stars after sampling them from an initial mass function. Because this procedure does not enforce coeval stellar evolution, some companions are more massive than stars that should remain on the main sequence in a 13.5-Gyr-old population.

The paper identifies this as a source of conservatively high reflex velocities and states that a physically consistent treatment requires synthesizing coeval binary systems directly. Incorporating binary evolution would also connect radial-velocity variability with photometric signatures and the altered masses, luminosities, survival probabilities, and orbital properties of interacting or evolved binaries.