An improved model of redshift-space distortions around voids:
  application to quintessence dark energy
  Using cosmic voids to probe the growth rate of cosmic structure, and hence
the nature of dark energy, is particularly interesting in the context of
modified gravity theories that rely on the screening mechanism. In this work we
improve the modelling of redshift-space distortions around voids in the dark
matter density field, and thus reduce systematic errors in the derivation of
cosmological parameters. We also show how specific types of voids can be used
to better probe the growth rate, using a flexible void finder. We apply our
results to test for a quintessence type of dark energy vs. a LCDM model, and
find a good agreement with the fiducial cosmology after implementing an
analytical correction to the radial velocity profiles around voids. We
additionally outline characteristic imprints of dark energy in the dark matter
velocity distributions around voids.
