A Northern Sky Survey at 15 GHz

Abstract

The 11th Cambridge (11C) survey is a large-scale radio survey that intends to map the entirety of the Northern hemisphere at a central frequency of 15.5GHz. The survey contains drift-scan data recorded using the Arcminute Microkelvin Imager Small Array (AMISA). Due to the challenging nature of high-frequency radio surveys, little is known about radio sources whose spectra rise with frequency. Catalogue comparisons with existing surveys will help to identify new inverted spectrum sources. Here we discuss the topic of catalogue comparisons and talk about how a comparison with a VLBI catalogue led to the discovery that 11C catalogues have been produced with incorrect source positions. We describe the steps used to find the source of the positional discrepancies, and talk about how we can mitigate incorrect positions from being included in future catalogues. We also introduce the topic of self-calibration strategies, applied to drift-scan data, that can be used to improve image fidelity of SA maps.

Date of Award	1 Aug 2023
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Keith Grainge (Supervisor) & Anna Scaife (Supervisor)