Recovering dark-matter clustering from galaxies with Gaussianization
  The Gaussianization transform has been proposed as a method to remove the
issues of scale-dependent galaxy bias and nonlinearity from galaxy clustering
statistics, but these benefits have yet to be thoroughly tested for realistic
galaxy samples. In this paper, we test the effectiveness of the Gaussianization
transform for different galaxy types by applying it to realistic simulated blue
and red galaxy samples. We show that in real space, the shapes of the
Gaussianized power spectra of both red and blue galaxies agree with that of the
underlying dark matter, with the initial power spectrum, and with each other to
smaller scales than do the statistics of the usual (untransformed) density
field. However, we find that the agreement in the Gaussianized statistics
breaks down in redshift space. We attribute this to the fact that red and blue
galaxies exhibit very different fingers of god in redshift space. After
applying a finger-of-god compression, the agreement on small scales between the
Gaussianized power spectra is restored. We also compare the Gaussianization
transform to the clipped galaxy density field and find that while both methods
are effective in real space, they have more complicated behaviour in redshift
space. Overall, we find that Gaussianization can be useful in recovering the
shape of the underlying dark matter power spectrum to k ~ 0.5 h/Mpc and of the
initial power spectrum to k ~ 0.4 h/Mpc in certain cases at z = 0.
