Improved Dark Energy Detection through the Polarization-assisted WMAP-NVSS ISW Correlation

TL;DR

This paper enhances dark energy detection by using CMB polarization to reduce noise in the ISW effect measurement, leading to more precise cross-correlation between WMAP data and NVSS radio sources.

Contribution

It introduces a polarization-assisted method to improve the accuracy of ISW effect detection through cross-correlation analysis.

Findings

Error bars reduced by 5-12% with polarization data

Improved statistical significance of ISW detection

Demonstrated effectiveness of polarization in noise suppression

Abstract

Integrated Sachs-Wolfe (ISW) effect can be estimated by cross-correlating Cosmic Microwave Background (CMB) sky with tracers of the local matter distribution. At late cosmic time, the dark energy induced decay of gravitation potential generates a cross-correlation signal on large angular scales. The dominant noise are the intrinsic CMB anisotropies from the inflationary epoch. In this Letter we use CMB polarization to reduce this intrinsic noise. We cross-correlate the microwave sky observed by Wilkinson Microwave Anisotropy Probe (WMAP) with the radio source catalog compiled by NRAO VLA Sky Survey (NVSS) to study the efficiency of the noise suppression . We find that the error bars are reduced about 5-12 %, improving the statistical power.