A deconvolution map-making method for experiments with circular scanning strategies

TL;DR

This paper introduces a deconvolution map-making algorithm capable of removing complex beam effects from circular scanning experiment data, demonstrated on Planck simulations, improving map accuracy at the cost of high computational demand.

Contribution

The paper presents a novel map-making method that jointly handles temperature, polarization, and beam deconvolution for experiments with circular scanning strategies.

Findings

Successfully removes beam effects from simulated maps.

Demonstrates impact of ignoring beam asymmetries.

Feasible application to Planck data despite computational costs.

Abstract

Aims. To investigate the performance of a deconvolution map-making algorithm for an experiment with a circular scanning strategy, specifically in this case for the analysis of Planck data, and to quantify the effects of making maps using simplified approximations to the true beams. Methods. We present an implementation of a map-making algorithm which allows the combined treatment of temperature and polarisation data, and removal of instrumental effects, such as detector time constants and finite sampling intervals, as well as the deconvolution of arbitrarily complex beams from the maps. This method may be applied to any experiment with a circular scanning-strategy. Results. Low-resolution experiments were used to demonstrate the ability of this method to remove the effects of arbitrary beams from the maps and to demonstrate the effects on the maps of ignoring beam asymmetries. Additionally, results are presented of an analysis of a realistic full-scale simulated data-set for the Planck LFI 30 GHz channel. Conclusions. Our method successfully removes the effects of the beams from the maps, and although it is computationally expensive, the analysis of the Planck LFI data should be feasible with this approach.