Cross-Correlation of Far-Infrared Background Anisotropies and CMB Lensing from Herschel and Planck satellites

TL;DR

This study measures the auto- and cross-correlation power spectra of the cosmic infrared background anisotropies and CMB lensing using Herschel and Planck data, achieving higher signal-to-noise ratios and improved constraints.

Contribution

It provides the largest CIB auto- and cross-power spectra measurements to date, with enhanced precision and new insights into the CIB and CMB lensing relationship.

Findings

CIB auto power spectra have SNR ~15.9, 15.7, 15.3 at 250, 350, 500 um.

CIB x CMB lensing cross spectra have SNR ~7.5, 7.0, 6.2.

Constraints on CIB parameters are improved by factors of 2 to 5.

Abstract

The cosmic infrared background (CIB) anisotropies and cosmic microwave background (CMB) lensing are powerful measurements for exploring the cosmological and astrophysical problems. In this work, we measure the auto-correlation power spectrum of the CIB anisotropies in the Herschel-SPIRE HerMES Large Mode Survey (HeLMS) field, and the cross power spectrum with the CMB lensing measurements from the Planck satellite. The HeLMS field covers more than 270 deg^2, which is much larger than the previous analysis. We use the Herschel Level 1 time stream data to merge the CIB maps at 250, 350, and 500 um bands, and mask the areas where the flux is greater than 3-sigma (~50 mJy/beam) or no measured data. We obtain the final CIB power spectra at 100<ell<20000 by considering several effects, such as beam function, mode coupling, transfer function, and so on. We also calculate the theoretical CIB auto- and cross-power spectra of CIB and CMB lensing by assuming that the CIB emissivity follows Gaussian distribution in redshift. We find that, for the CIB auto power spectra, we obtain the signal to noise ratio (SNR) of 15.9, 15.7, and 15.3 at 250, 350, and 500 um, and for the CIBxCMB lensing power spectra, SNR of 7.5, 7.0, and 6.2 at 250, 350, and 500 um, respectively. Comparing to previous works, the constraints on the relevant CIB parameters are improved by factors of 2~5 in this study.