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Title: Cross-correlation of Planck CMB lensing with DESI-like LRGs
ABSTRACT Cross-correlations between the lensing of the cosmic microwave background (CMB) and other tracers of large-scale structure provide a unique way to reconstruct the growth of dark matter, break degeneracies between cosmology and galaxy physics, and test theories of modified gravity. We detect a cross-correlation between Dark Energy Spectroscopic Instrument (DESI)-like luminous red galaxies (LRGs) selected from DECam Legacy Survey imaging and CMB lensing maps reconstructed with the Planck satellite at a significance of S/N = 27.2 over scales ℓmin = 30, ℓmax = 1000. To correct for magnification bias, we determine the slope of the LRG cumulative magnitude function at the faint limit as s = 0.999 ± 0.015, and find corresponding corrections of the order of a few per cent for $$C^{\kappa g}_{\ell }, C^{gg}_{\ell }$$ across the scales of interest. We fit the large-scale galaxy bias at the effective redshift of the cross-correlation zeff ≈ 0.68 using two different bias evolution agnostic models: a HaloFit times linear bias model where the bias evolution is folded into the clustering-based estimation of the redshift kernel, and a Lagrangian perturbation theory model of the clustering evaluated at zeff. We also determine the error on the bias from uncertainty in the redshift distribution; within this error, the two methods show excellent agreement with each other and with DESI survey expectations.  more » « less
Award ID(s):
1713791
PAR ID:
10225529
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
501
Issue:
4
ISSN:
0035-8711
Page Range / eLocation ID:
6181 to 6198
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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