Coffee talks
Friday 05/06/2026 @ 11:30, Sala riunioni quarto piano e on-line (meet.google.com/sue-bwvk-axf)
Jahang Prathap (Macquarie University, Sydney, Australia), "Tracing the Balance of Power in Galaxies using Machine Learning"
Disentangling the interplay between star formation and nuclear activity is key to understanding how active galactic nuclei (AGN) shape galaxy evolution. We apply unsupervised machine-learning clustering to multiwavelength (optical, infrared, and radio) AGN diagnostics to quantify the fractional energy contributions from these processes in radio-detected galaxies. Using data from the GAMA G09 and G23 fields, the Evolutionary Map of the Universe (EMU), and WISE, our method recovers ~90% of star-forming galaxies and ~80% of the AGN identified by traditional diagnostics. We introduce a new three-dimensional IR-radio diagnostic (W1-W2 colour, W2 magnitude, 1.4 GHz flux density) that selects radio AGN with ~90% reliability, and achieves ~90% completeness. Finally, we present a probabilistic EMU catalogue assigning fractional AGN and star-formation activity across optical, IR, and radio regimes. Our results support a fractional, data-driven view of galaxy activity, providing new tools to trace AGN-galaxy coevolution in the era of EMU and the SKA.