Improved Method for Detecting Local Discontinuities in CMB data by Finite Differencing

TL;DR

This paper introduces a finite differencing technique in harmonic space to detect temperature discontinuities in CMB data, aiming to identify potential signs of new physics like cosmic defects.

Contribution

The paper presents a novel finite differencing method with harmonic space noise regularization for detecting discontinuities in CMB maps, improving sensitivity to cosmic defects.

Findings

Successfully applied to WMAP 7-year data

Detected potential temperature discontinuities

Method enhances detection of cosmic defects

Abstract

An unexpected distribution of temperatures in the CMB could be a sign of new physics. In particular, the existence of cosmic defects could be indicated by temperature discontinuities via the Kaiser-Stebbins effect. In this paper, we show how performing finite differences on a CMB map, with the noise regularized in harmonic space, may expose such discontinuities, and we report the results of this process on the 7-year Wilkinson Microwave Anisotropy Probe data.