PT Journal
AU Villanueva-Domingo, P
   Gnedin, NY
   Mena, O
TI Warm Dark Matter and Cosmic Reionization
SO Astrophysical Journal
JI Astrophys. J.
PY 2018
BP 139
EP 7pp
VL 852
IS 2
DI 10.3847/1538-4357/aa9ff5
LA English
DE cosmology: theory; galaxies: formation; intergalactic medium; large-scale structure of universe; methods: numerical
AB In models with dark matter made of particles with keV masses, such as a sterile neutrino, small-scale density perturbations are suppressed, delaying the period at which the lowest mass galaxies are formed and therefore shifting the reionization processes to later epochs. In this study, focusing on Warm Dark Matter (WDM) with masses close to its present lower bound, i.e., around the 3. keV region, we derive constraints from galaxy luminosity functions, the ionization history and the Gunn-Peterson effect. We show that even if star formation efficiency in the simulations is adjusted to match the observed UV galaxy luminosity functions in both CDM and WDM models, the full distribution of Gunn-Peterson optical depth retains the strong signature of delayed reionization in the WDM model. However, until the star formation and stellar feedback model used in modern galaxy formation simulations is constrained better, any conclusions on the nature of dark matter derived from reionization observables remain model-dependent.
ER