Zeus21: Lightning-fast simulations of cosmic dawn and reionization
Zeus21 encodes the effective model for the 21-cm power spectrum and global signal from Muñoz 2023a. The goal is to capture all the nonlocal and nonlinear physics of cosmic dawn in a light and fully Pythonic code. Zeus21 takes advantage of the approximate log-normality of the star-formation rate density (SFRD) during cosmic dawn to compute the 21-cm power spectrum analytically. It agrees with more expensive semi-numerical simulations to roughly 10% precision, but has comparably negligible computational cost (~ s) and memory requirements. Now Zeus21 can also predict galaxy UV luminosity functions (UVLFs) and their linear clustering (galaxy bias) at any z, see Muñoz et al. 2023b for the implementation and application to JWST. Now Zeus21 includes Population III stars with inhomogeneous Lyman-Werner feedback and relative velocities (with their fluctuations), as described in Cruz et al. 2024.
Zeus21 (Zippy Early-Universe Solver for 21-cm) pairs well with data from HERA, but can be used for any 21-cm inference or prediction. Current capabilities include finding the 21-cm power spectrum (at a broad range of k and z), the global signal, IGM temperatures (Tk, Ts, Tcolor), neutral fraction xHI, Lyman-alpha fluxes, and the evolution of the SFRD; all across cosmic dawn z=5-35. Zeus21 can use three different astrophysical models, one of which emulates 21cmFAST, and can vary the cosmology through CLASS.
Full documentation (with installation instructions, tutorials, and full api description) can be found on ReadTheDocs.