Blind Search for Variability in Planck Data

TL;DR

This paper introduces a method to detect variable and transient sources across the entire sky using Planck data, addressing challenges like instrumental noise and systematic effects, to explore variability on time scales from hours to years.

Contribution

It presents a novel full-sky blind search technique for variable sources in Planck data, accounting for instrumental noise and systematic effects.

Findings

Method successfully identifies variable sources across all Planck frequencies.

Addresses systematic effects caused by non-symmetric beam shapes.

Enables variability studies on time scales from hours to several years.

Abstract

The sky is full of variable and transient sources on all time scales, from milliseconds to decades. Planck's regular scanning strategy makes it an ideal instrument to search for variable sky signals in the millimetre and submillimetre regime, on time scales from hours to several years. A precondition is that instrumental noise and systematic effects, caused in particular by non-symmetric beam shapes, are properly removed. We present a method to perform a full sky blind search for variable and transient objects at all Planck frequencies.