Thursday

Cross-identification of radio sources with optical and infrared catalogues is essential for determining host properties and distances, leading to intrinsic properties such as luminosity and size; but it is far from straight forward. For simple, compact or isolated sources this can be done in an automated fashion. For extended sources or those which contain multiple components this becomes more complicated and has more often been achieved through human classification. As surveys become larger and sources more numerous this method becomes less efficient. The LOFAR Two metre Sky Survey (LoTSS) is the largest radio survey to date in terms of numbers of sources and data volume and is sensitive to both compact and extended emission, making it ideal for the study of radio sources. Using the LoTSS data release 1, we have applied the innovative idea of ridgelines, tracing the path of a jet, to link radio sources to their host galaxies. It is important to be able to correctly catalogue source populations and retrieve their properties, in SKA pathfinder surveys, to enable accurate modelling.
This talk will introduce ridgelines in the context of extended radio sources, and how they have been successfully integrated into established methods for cross-identification. I will discuss the results from LoTSS DR1 demonstrating the effectiveness of the method with a sample of sources with known hosts. I will also discuss how this new statistical method can be applied to current and upcoming surveys such as LoTSS DR2, and the adaption to MeerKAT. This talk will demonstrate improvements in the cross-identification process which can be applied across surveys to reduce the time and resources spent on alternative methods, such as citizen science approaches; providing a thorough data set upon which to build precise models of the radio sky.