The Cosmic Lyman-alpha Transfer (COLT) code 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.



If you have any issues obtaining, compiling, or running the code, please consult the below documentation, or let us know by email (Aaron Smith, arsmith@mit.edu). We are also open to collaboration, which is particularly encouraged when using or implementing new features.