A scenario for ultra-diffuse satellite galaxies with low velocity
  dispersions: the case of [KKS 2000]04
  A scenario for achieving a low velocity dispersion for the galaxy [KKS
2000]04 (aka NGC 1052-DF2) and similar galaxies is presented.
  A progenitor halo corresponding to a $z=0$ halo of mass $\sim 5\times
10^{10}\; \textrm{M}_\odot$ and a low concentration parameter (but consistent
with cosmological simulations) infalls onto a Milky Way-size host at early
times. {Substantial removal of cold gas} from the inner regions by supernova
feedback and ram pressure, assisted by tidal stripping of the dark matter in
the outer regions, leads to a substantial reduction of the velocity dispersion
of stars within one effective radius. In this framework, the observed stellar
content of [KKS 2000]04 is associated with a progenitor mass close to that
inferred from the global stellar-to-halo-mass ratio. As far as the implications
of kinematics are concerned, even if at a $\sim 20 $ Mpc distance, it is argued
that [KKS 2000]04 is no more peculiar than numerous early type galaxies with
seemingly little total dark-matter content.
