Enabling the Next Generation of 21 cm Cosmology: Precision Analysis Techniques for Radio Cosmology Observations

Abstract

Detecting the EoR will require extremely precise measurements. The signal is very faint and is obscured by intervening emission, or foregrounds, that are 4-5 orders of magnitude brighter. Thus far, analyses have not achieved the precision required to measure the EoR signal. Calibration precision is a dominant limitation of these analyses. This thesis focuses on understanding and mitigating calibration error for interferometric measurement of the EoR power spectrum signal. We propose a novel approach to calibration, called unified calibration, that is based on Bayesian statistics. We show in simulation that unified calibration outperforms the established techniques in the field. Additionally, we present results that expand and improve the calibration sky model. Precision calibration requires an accurate and complete model of the sky signal, and we examine the impact of sky model error on calibration performance. We describe the development of a new polarized imaging pipeline that we then use to map diffuse emission at 182 MHz across 11,000 square degrees of the Southern Hemisphere sky. The map is presented in all four Stokes parameters and contains emission on scales of 1-9 degrees. We discuss the implementation of this diffuse map in calibration and explore its effect on calibration performance.