PUMA: The Positional Update and Matching Algorithm

Abstract

We present new software to cross-match low-frequency radio catalogues: the Positional Update and Matching Algorithm (PUMA). PUMA combines a positional Bayesian probabilistic approach with spectral matching criteria, allowing for confusing sources in the matching process. We go on to create a radio sky model using PUMA based on the Murchison Widefield Array Commissioning Survey, and are able to automatically cross-match 98.5% of sources. Using the characteristics of this sky model, we create simple simulated mock catalogues on which to test PUMA, and find that PUMA can reliably find the correct spectral indices of sources, along with being able to recover ionospheric offsets. Finally, we use this sky model to calibrate and remove foreground sources from simulated interferometric data, generated using OSKAR (the Oxford University visibility generator). We demonstrate that there is a substantial improvement in foreground source removal when using higher frequency and higher resolution source positions, even when correcting positions by an average of 0.3 given a synthesized beam-width of 2.3.

Accepted for publication in Publications of the Astronomical Society of Australia (PASA) - 34 pages - 20 figures - PUMA github repository: https://github.com/JLBLine/PUMA

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Cited by in corpus (4)

• Characterisation of the ionosphere above the Murchison Radio Observatory using the Murchison Widefield Array
• A high resolution foreground model for the MWA EoR1 field: model and implications for EoR power spectrum analysis
• A southern-sky total intensity source catalogue at 2.3 GHz from S-band Polarisation All-Sky Survey data
• Building models for extended radio sources: implications for Epoch of Reionisation science