Tidal forces from the wake of dynamical friction: warps, lopsidedness
  and kinematic misalignment
  A galaxy moving through a background of dark matter particles, induces an
overdensity of these particles or a wake behind it. The back reaction of this
wake on the galaxy is a force field that can be decomposed into an effective
deceleration (called dynamical friction) and a tidal field. In this paper we
determine the tidal forces, thus generated on the galaxy, and the resulting
observables, which are shown to be warps, lopsidedness and/or
kinematic-photometric position angle misalignments. We estimate the magnitude
of the tidal-like effects needed to reproduce the observed warp and
lopsidedness on the isolated galaxy IC 2487. Within a realistic range of dark
matter distribution properties the observed warped and lopsided kinematical
properties of IC 2487 is possible to reproduce (the background medium of dark
matter particles has a velocity dispersion of $\lesssim 80\,{\rm km\,s^{-1}}$
and the density $10^4-10^5~{\rm M_\odot\,kpc^{-3}}$, more likely at the lower
end). We conclude that the proposed mechanism can generate warps, lopsidedness
and misalignments observed in isolated galaxies or galaxies in loose groups.
The method can be used also to constrain dark matter spatial and velocity
distribution properties.
