Simulating intergalactic gas for DESI-like small scale Lyman{\alpha} forest observations

Understand

Measurements of the Ly$\alpha$ forest based on large numbers of quasar spectra from sky surveys such as SDSS/eBOSS accurately probe the distribution of matter on small scales and thus provide important constraints on several ingredients of the cosmological model.

• A main summary statistic derived from those measurements is the one-dimensional power spectrum, P1D, of the Ly$\alpha$ absorption.
• However, model predictions for P1D rely on expensive hydrodynamical simulations of the intergalactic medium, which was the limiting factor in previous analyses.
• Datasets from upcoming surveys such as DESI will push observational accuracy near the 1%-level and probe even smaller scales.