Ranchod, ShilpaMao, S. A.Deane, RogerSridhar, Sarrvesh S.Damas-Segovia, AncorLivingston, JackMa, Y. K.2024-08-222024-08-222024-06Ranchod, S., Mao, S.A., Deane, R. et al. 2024, 'The Galactic latitude dependency of faraday complexity in the S-PASS/ATCA RM catalogue', Astronomy and Astrophysics, vol. 686, art. A104, pp. 1-16, doi : 10.1051/0004-6361/202348993.2329-1273 (print)2329-1265 (online)10.1051/0004-6361/202348993http://hdl.handle.net/2263/97822The S -band Polarisation All Sky Survey (SPASS/ATCA) rotation measure (RM) catalogue is the largest broadband RM catalogue to date, increasing the RM density in the sparse southern sky. Through analysis of this catalogue, we report a latitude dependency of the Faraday complexity of polarised sources in this catalogue within 10◦ of the Galactic plane towards the inner Galaxy. In this study, we aim to investigate this trend with follow-up observations using the Australia Telescope Compact Array (ATCA). We observe 95 polarised sources from the SPASS/ATCA RM catalogue at 1.1–3.1 GHz with ATCA’s 6 km configuration. We present Stokes QU fitting results and a comparative analysis with the SPASS/ATCA catalogue. We find an overall decrease in complexity in these sources with the higher angular resolution observations, with a complexity fraction of 42%, establishing that the majority of the complexity in the SPASS/ATCA sample is due to the mixing-in of diffuse Galactic emission at scales θ > 2.8 0 . Furthermore, we find a correlation between our observed small-scale complexity θ < 2.8 0 and the Galactic spiral arms, which we interpret to be due to Galactic turbulence or small-scale polarised emission. These results emphasise the importance of considering the maximum angular scale to which the observations are sensitive in the classification of Faraday complexity; the effect of which can be more carefully investigated with SKA-precursor and pathfinder arrays (e.g. MeerKAT and ASKAP).en© 2024. The Authors.Polarization – techniquesPolarimetric – GalaxyGeneral – radio continuumGalaxiesArticle