Dr. Pedro Italo de Araujo Ferreira (Federal University of Sergipe, Brazil)
10 December 2025
11:30, Aula Piazzi
Abstract:
Understanding how galaxy scaling relations emerge requires a framework in which simulations and real galaxies can be compared on equal footing. We present the virtual-ETG catalogue, a realistic sample of Early-Type Galaxies constructed from the IllustrisTNG100-1 simulation through an observational-like pipeline. Galaxies are projected along three orthogonal directions, their surface-brightness profiles are modelled with Sersic fits, and aperture velocity dispersions are measured along the corresponding line of sight, with central dynamics corrected for force softening. Central mass-density profiles are described by power-law models, while intrinsic three-dimensional masses are retained from the simulation. The final sample of 10121 ETGs at z ≤ 0.1 reproduces a wide range of observed photometric and dynamical trends. Classic relations, such as the size-mass relation, the Faber-Jackson relation, and correlations between effective radius, surface brightness, and stellar mass, are naturally recovered. The catalogue also captures the connection between internal structure and kinematics, including the dependence of total density slopes on Sersic index, mass, and velocity dispersion. These trends offer a coherent picture linking galaxy structure to assembly pathways and provide a controlled environment for isolating projection effects and physical drivers. By bringing simulated galaxies closer to observational conditions, the virtual-ETG catalogue creates a bridge between hydrodynamical simulations and real ETG populations. Its scaling relations form a foundation for studies of galaxy evolution and serve as a benchmark for testing observational inferences, reliability of the physics implemented in the simulations and for the application of Machine Learning approaches in forthcoming large surveys.