Introducing Decorated HODs: modeling assembly bias in the galaxy-halo connection

Understand

The connection between galaxies and dark matter halos is often inferred from data using probabilistic models, such as the Halo Occupation Distribution (HOD).

• Conventional HOD formulations assume that only halo mass governs the galaxy-halo connection.
• Violations of this assumption, known as galaxy assembly bias, threaten the HOD program.
• We introduce decorated HODs, a new, flexible class of models designed to account for assembly bias.