Where are the Luminous Red Galaxies (LRGs)? Using correlation
  measurements and lensing to relate LRGs to dark matter halos
  Nonlinear redshift-space distortions, the Finger-of-God (FoG) effect, can
complicate the interpretation of the galaxy power spectrum. Here, we
demonstrate the method proposed by Hikage et al. (2012) to use complimentary
observations to directly constrain this effect on the data. We use catalogs of
Luminous Red Galaxies (LRGs) and photometric galaxies from the SDSS DR7 to
measure the redshift-space power spectrum of LRGs, the cross-correlation of
LRGs with the shapes of background photometric galaxies (galaxy-galaxy weak
lensing), and the projected cross-correlation of LRGs with photometric galaxies
having similar photometric redshifts to the LRG spectroscopic redshift. All of
these measurements use a reconstructed halo field. While we use the position of
each LRG for single LRG systems, we compare the measurements using different
halo-center proxies for multiple-LRG systems (4.5 per cent of all the halos):
the brightest LRG position (BLRG), the faintest LRG position (FLRG) and their
arithmetical mean position (Mean), respectively, in each system. We find
significant differences in the measured correlations of different centers,
showing consistent off-centering effects in the three observables. By comparing
the measurements with a halo model that treats the satellite photometric
galaxies as being distributed according to a generalized NFW profile, we find
that about 40 (70) per cent of BLRGs (FLRGs) are off-centered satellite
galaxies in the multiple-LRG systems. The satellite LRGs have typical
off-centering radius of about 400 kpc/h, and velocity dispersion of about 500
km/s in host halos with a mean mass of 1.6x10^14 Ms/h. We show that, if LRGs in
the single LRG systems have similar offsets, the residual FoG contamination in
the LRG power spectrum can be significant at k>0.1 h/Mpc, which may cause a
bias in cosmological parameters such as the neutrino mass.
