Classification and alignment of DRAGNs

Abstract

The study of Active Galactic Nuclei formation and evolution is important in modern astronomy, as they represent an evolutionary stage in every galaxy, and thus are important to understand the formation and evolution of galaxies. However, there is not yet a full understanding of the physics and evolution of the population that emit brightly at radio wavelengths. In order to properly compare observations with theory, a large survey of radio-loud galaxies is required. In this project, I will be studying Double Radio sources Associated with Galactic Nuclei, as I wanted to learn more about them. I will be focusing on the Fanaroff-Riley types I and II in particular. I study their luminosities and find a large overlap between the two classes, moreso than previous studies, with no obvious 'break'. I also study their alignment in the sky, and find significant alignment up to 4 degrees. This is to test claims that the position angles of radio galaxies are aligned over cosmic distances. Such an alignment could only have arisen at the time of formation which would perhaps be able to provide some insight into early formation of supermassive black holes. I will be using data from the Evolutionary Map of the Universe pilot survey that was obtained with CSIRO's Australian Square Kilometre Array Pathfinder, as well as GAMA-23 Early Science. A survey of this size will allow study of a large sample of sources that are free from selection effects and biases of previous and older studies and will be a valuable training set for my colleagues who are developing machine learning algorithms to find and classify radio sources.

Date of Award	2023
Original language	English