In this third paper of the series , we investigate the effects of warm dark matter with a particle mass of m _ { \mathrm { WDM } } = 3 \mathrm { keV } on the smallest galaxies in our Universe .
We present a sample of 21 hydrodynamical cosmological simulations of dwarf galaxies and 20 simulations of satellite-host galaxy interaction that we performed both in a Cold Dark Matter ( CDM ) and Warm Dark Matter ( WDM ) scenario .
In the WDM simulations , we observe a higher critical mass for the onset of star formation .
Structure growth is delayed in WDM , as a result WDM haloes have a stellar population on average two Gyrs younger than their CDM counterparts .
Nevertheless , despite this delayed star formation , CDM and WDM galaxies are both able to reproduce the observed scaling relations for velocity dispersion , stellar mass , size , and metallicity at z = 0 .
WDM satellite haloes in a Milky Way mass host are more susceptible to tidal stripping due to their lower concentrations , but their galaxies can even survive longer than the CDM counterparts if they live in a dark matter halo with a steeper central slope .
In agreement with our previous CDM satellite study we observe a steepening of the WDM satellites ’ central dark matter density slope due to stripping .
The difference in the average stellar age for satellite galaxies , between CDM and WDM , could be used in the future for disentangling these two models .