Cross-correlation of CFHTLenS galaxy catalogue and Planck CMB lensing using the halo model prescription

Abstract

Aims: I cross-correlate the galaxy counts from the Canada-France Hawaii Telescope Lensing Survey (CFHTLenS) galaxy catalogue and cosmic microwave background (CMB) convergence from the Planck data releases 1 (2013) and 2 (2015).
Methods: I improve on an earlier study by computing an analytic covariance from the halo model, implementing simulations to validate the theoretically estimated error bars and the reconstruction method, fitting both a galaxy bias and a cross-correlation amplitude using the joint cross and galaxy auto-correlation, and performing a series of null tests.
Results: Using a Bayesian analysis, I find a galaxy bias b = 0.92_-0.02^+0.02 and a cross-correlation amplitude A = 0.85_-0.16^+0.15 for the 2015 release, whereas for the 2013 release, I find b = 0.93_-0.02^+0.02 and A = 1.05_-0.15^+0.15.
Conclusions: I thus confirm the difference between the two releases found earlier, although both values of the amplitude now appear to be compatible with the fiducial value A = 1.

Based on observations obtained with Planck (http://www.esa.int/Planck), an ESA science mission with instruments and contributions directly funded by ESA Member States, NASA, and Canada. A copy of the code is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/584/A53