Modeling CMB lensing cross correlations with CLEFT. Issue 8 (4th August 2017)

• Record Type: Journal Article
• Authors: Modi, Chirag; White, Martin; Vlah, Zvonimir
• Is Part Of: Journal of cosmology and astroparticle physics. Volume 2017:Issue 8(2017)
• Page Start: 009
• Page End: 009
• Publication Date: 2017-08-04
• Subjects: Cosmology -- Periodicals; Astrophysics -- Periodicals; 523.0105
• DOI: 10.1088/1475-7516/2017/08/009
• Languages: English
• ISSNs: 1475-7516

Abstract

Abstract: A new generation of surveys will soon map large fractions of sky to ever greater depths and their science goals can be enhanced by exploiting cross correlations between them. In this paper we study cross correlations between the lensing of the CMB and biased tracers of large-scale structure at highz z . We motivate the need for more sophisticated bias models for modeling increasingly biased tracers at these redshifts and propose the use of perturbation theories, specifically Convolution Lagrangian Effective Field Theory (CLEFT). Since such signals reside at large scales and redshifts, they can be well described by perturbative approaches. We compare our model with the current approach of using scale independent bias coupled with fitting functions for non-linear matter power spectra, showing that the latter will not be sufficient for upcoming surveys. We illustrate our ideas by estimating\sigma_8 σ8 from the auto- and cross-spectra of mock surveys, finding that CLEFT returns accurate and unbiased results at highz z . We discuss uncertainties due to the redshift distribution of the tracers, and several avenues for future development.