JWST high-redshift galaxy constraints on warm and cold dark matter models

Abstract

Context. Warm dark matter is a possible alternative to cold dark matter to explain cosmological structure formation. Aims. We study the implications of the latest JWST data on the nature of dark matter. Methods. We compare properties of high-redshift galaxies observed by JWST with hydrodynamical simulations, in the standard cold dark matter model and in warm dark matter models with a suppressed linear matter power spectrum Results. We find that current data are neither in tension with cold dark matter nor with warm dark matter models with mWDM >  2 keV, since they probe bright and rare objects whose physical properties are similar in the different scenarios. Conclusions. We also show how two observables, the galaxy luminosity functions and the galaxy correlation function at small scales of faint objects, can be promising tools for discriminating between the different dark-matter scenarios. Further hints may come from early stellar-mass statistics and galaxy CO emission.