Implementing Molecular Hydrogen in Hydrodynamic Simulations of Galaxy Formation

Understand

Motivated by the observed connection between molecular hydrogen (H2) and star formation, we present a method for tracking the non-equilibrium abundance and cooling processes of H2 and H2-based star formation in Smoothed Particle Hydrodynamic simulations.

• The local abundances of H2 are calculated by integrating over the hydrogen chemical network.
• This calculation includes the gas-phase and dust grain formation of H2, shielding of HI and H2, and photodissociation of H2 by Lyman-Werner radiation from nearby stellar populations.
• Because this model does not assume equilibrium abundances, it is particularly well suited for simulations that model low-metallicity environments, such as dwarf galaxies and the early Universe.