Cataloguing the radio-sky with unsupervised machine learning: A new approach for the SKA era

T. J. Galvin, M. T. Huynh, R. P. Norris, X. R. Wang, E. Hopkins, K. Polsterer, N. O. Ralph, A. N. O'brien, G. H. Heald

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)


We develop a new analysis approach towards identifying related radio components and their corresponding infrared host galaxy based on unsupervised machine learning methods. By exploiting Parallelized rotation and flipping INvariant Kohonen maps (pink), a self-organizing map (SOM) algorithm, we are able to associate radio and infrared sources without the a priori requirement of training labels. We present an example of this method using 894 415 images from the Faint Images of the Radio-Sky at Twenty centimeters (FIRST) and Wide-field Infrared Survey Explorer (WISE) surveys centred towards positions described by the FIRST catalogue. We produce a set of catalogues that complement FIRST and describe 802 646 objects, including their radio components and their corresponding AllWISE infrared host galaxy. Using these data products, we (i) demonstrate the ability to identify objects with rare and unique radio morphologies (e.g. 'X'-shaped galaxies, hybrid FR I/FR II morphologies), (ii) can identify the potentially resolved radio components that are associated with a single infrared host, (iii) introduce a 'curliness' statistic to search for bent and disturbed radio morphologies, and (iv) extract a set of 17 giant radio galaxies between 700 and 1100 kpc. As we require no training labels, our method can be applied to any radio-continuum survey, provided a sufficiently representative SOM can be trained.

Original languageEnglish
Pages (from-to)2730-2758
Number of pages29
JournalMonthly Notices of the Royal Astronomical Society
Issue number3
Publication statusPublished - 1 Sept 2020


Dive into the research topics of 'Cataloguing the radio-sky with unsupervised machine learning: A new approach for the SKA era'. Together they form a unique fingerprint.

Cite this