Recently, several studies reported a significant discrepancy between the
clustering and lensing of the Baryon Oscillation Spectroscopic Survey (BOSS)
galaxies in the Planck cosmology. We construct a simple yet powerful
model based on the linear theory to assess whether this discrepancy points
toward deviations from Planck. Focusing on scales 10<R<30hβ1Mpc, we model the amplitudes of clustering and lensing of BOSS
LOWZ galaxies using three parameters: galaxy bias bgβ, galaxy-matter
cross-correlation coefficient rgmβ, and A, defined as the ratio
between the true and Planck values of Ο8β. Using the
cross-correlation matrix as a diagnostic, we detect systematic uncertainties
that drive spurious correlations among the low-mass galaxies. After building a
clean LOWZ sample with rgmββΌ1, we derive a joint constraint of
bgβ and A from clustering+lensing, yielding
bgβ=2.47β0.30+0.36β and A=0.81β0.09+0.10β, i.e., a
2Ο tension with Planck. However, due to the strong degeneracy
between bgβ and A, systematic uncertainties in bgβ
could masquerade as a tension with A=1. To ascertain this possibility, we
develop a new method to measure bgβ from the cluster-galaxy
cross-correlation and cluster weak lensing using an overlapping cluster sample.
By applying the independent bias measurement (bgβ=1.76Β±0.22) as a
prior, we successfully break the degeneracy and derive stringent constraints of
bgβ=2.02β0.15+0.16β and A=0.96Β±0.07. Therefore, our result
suggests that the large-scale clustering and lensing of LOWZ galaxies are
consistent with Planck, while the different bias estimates may be
related to some observational systematics in the target selection.Comment: 8 pages, 5 figures, comments welcome