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

TL;DR

This study compares JWST high-redshift galaxy observations with simulations to evaluate cold and warm dark matter models, identifying potential discriminators like luminosity functions and galaxy correlations.

Contribution

It demonstrates that current JWST data do not exclude warm dark matter models with mWDM > 2 keV and highlights observables that could differentiate dark matter scenarios.

Findings

Current data are consistent with both CDM and warm dark matter models with mWDM > 2 keV.

Galaxy luminosity functions and small-scale correlation functions can help distinguish dark matter types.

Early stellar-mass and CO emission data may provide additional constraints.

Abstract

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. We find that current data are not 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. 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 models. Further hints may come from early stellar-mass statistics and galaxy CO emission.