HIILines analytically models lines emitted by the ionized interstellar medium (ISM). It covers [OIII], [OII], H_α, and H_β lines. The strength of HIILines is its high computational efficiency. It can be used for galaxy spectroscopic survey measurement interpolations assuming a one-zone picture and galaxy line emission measurement design and forecasts. HIILines also performs post-processing of hydrodynamical galaxy formation simulations for ISM emission lines.

COLT (Cosmic Lyman-alpha Transfer) is a Monte Carlo radiative transfer (MCRT) solver for post-processing hydrodynamical simulations on arbitrary grids. These include a plane parallel slabs, spherical geometry, 3D Cartesian grids, adaptive resolution octrees, unstructured Voronoi tessellations, and secondary outputs. COLT also includes several visualization and analysis tools that exploit the underlying ray-tracing algorithms or otherwise benefit from an efficient hybrid MPI + OpenMP parallelization strategy within a flexible C++ framework.