10C Survey of Radio Sources at 15.7 GHz: I - Observing, mapping and source extraction

TL;DR

This paper details the methods for observing, mapping, and extracting sources from a highly sensitive 15.7 GHz radio survey covering 27 square degrees, establishing a foundation for analyzing radio source populations.

Contribution

It introduces systematic techniques for radio source detection and cataloguing at 15.7 GHz, including simulations and methods for handling complex source structures.

Findings

Most sensitive survey above 1.4 GHz for large areas

Development of new source extraction and mapping procedures

Validation of methods through simulations

Abstract

We have observed an area of approximatley 27 deg^2 to an rms noise level of less than 0.2 mJy at 15.7 GHz, using the Arcminute Microkelvin Imager Large Array. These observations constitute the most sensitive radio-source survey of any extent (greater than approximately 0.2 deg^2) above 1.4 GHz. This paper presents the techniques employed for observing, mapping and source extraction. We have used a systematic procedure for extracting information and producing source catalogues, from maps with varying noise and uv-coverage. We have performed simulations to test our mapping and source-extraction procedures, and developed methods for identifying extended, overlapping and spurious sources in noisy images. In an accompanying paper, AMI Consortium: Davies et al. 2010, the first results from the 10C survey, including the deep 15.7-GHz source count, are presented.