A detection of the integrated Sachs-Wolfe imprint of cosmic superstructures using a matched-filter approach

TL;DR

This paper introduces a novel matched-filter method for detecting the ISW imprint of cosmic superstructures on the CMB, achieving a significant detection consistent with the DM model.

Contribution

The paper presents a new matched-filter technique for ISW detection that avoids a posteriori bias and applies it to Planck data, confirming DM predictions.

Findings

Detected ISW signal with 3.1c sigma significance.

Measured ISW amplitude of 1.64b1 0.53.

Result consistent with DM model.

Abstract

We present a new method for detection of the integrated Sachs-Wolfe (ISW) imprints of cosmic superstructures on the cosmic microwave background, based on a matched filtering approach. The expected signal-to-noise ratio for this method is comparable to that obtained from the full cross-correlation, and unlike other stacked filtering techniques it is not subject to an a posteriori bias. We apply this method to Planck CMB data using voids and superclusters identified in the CMASS galaxy data from the Sloan Digital Sky Survey Data Release 12, and measure the ISW amplitude to be $A_\mathrm{ISW}=1.64\pm0.53$ relative to the $\Lambda$CDM expectation, corresponding to a $3.1\sigma$ detection. In contrast to some previous measurements of the ISW effect of superstructures, our result is in agreement with the $\Lambda$CDM model.