Radio-loud AGN morphology and host-galaxy properties in the LOFAR Two-Metre Sky Survey Data Release 2

Radio-loud active galaxies (RLAGN) can exhibit various morphologies. The Fanaroff-Riley (FR) classifications, which are defined by the locations of peaks in surface brightness, have been applied to many catalogues of RLAGN. The FR classifications were initially found to correlate with radio luminosity. However, recent surveys have demonstrated that radio luminosity alone does not reliably predict radio morphology. We have devised a new semi-automated method involving ridgeline characterizations to compile the largest known classified catalogue of RLAGN to date, with data from the LOFAR (LOw Frequency ARray) Two-metre Sky Survey Data Release 2. We reassess the FR divide and its cause by examining the physical and host galaxy properties of 3590 FRIIs (FR type II) and 2354 FRIs (FR type I) (at). We find that RLAGN near the FR divide with WHz-1 are more likely to show FRI over FRII morphology if they occupy more massive host galaxies. We find no correlation, when considering selection effects, between the FR break luminosity and stellar mass or host-galaxy rest-frame absolute magnitude. Overall, we find the cause of the different radio morphologies in this sample to be complex. Considering sources near the FR divide with WHz-1, we find evidence to support the inner environment having a role in determining jet disruption. We make available a public catalogue of morphologies for our sample, which will be of use for future investigations of RLAGN and their impact on their surroundings.