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Abstract For the first time, systematic studies of dwarf galaxies are being conducted throughout the Local Volume, including the dwarf satellites of the nearby giant elliptical galaxy Centaurus A (NGC 5128). Given Centaurus A's mass (roughly 10 times larger than that of the Milky Way), AGN activity, and recent major mergers, investigating the dwarf galaxies of Centaurus A and their star formation physics is imperative. However, simulating the faintest dwarfs around a galaxy of Centaurus A's mass with sufficient resolution in a hydrodynamic simulation is computationally expensive and currently infeasible. In this study, we seek to reproduce the properties of Centaurus A dwarfs using the semianalytic modelGalacticusto model dwarfs within a 700 kpc region around Centaurus A, corresponding approximately to its splashback radius. We investigate the effects of host halo mass and environment and predict observable properties of Centaurus A dwarfs using astrophysical prescriptions and parameters previously tuned to match properties of the Milky Way’s satellite galaxies. This approach allows us to approximately replicate cumulative luminosity functions, and luminosity–metallicity and luminosity–half-light-radii relations observed in the Centaurus A satellites. We provide predictions for the velocity dispersions, and star formation histories of Centaurus A dwarfs. The agreement between our predicted star formation histories for Centaurus A dwarfs and those of the Milky Way dwarfs implies the presence of universal processes governing star formation in dwarf galaxies. Overall, our findings shed light on the star formation physics of dwarf galaxies in the Centaurus A system, revealing insights into their properties and dependence on the host environment. 

ABSTRACT In this study, we modify the semi-analytic model galacticus in order to accurately reproduce the observed properties of dwarf galaxies in the Milky Way. We find that reproducing observational determinations of the halo occupation fraction and mass–metallicity relation for dwarf galaxies requires us to include H2 cooling, an updated ultraviolet background radiation model, and to introduce a model for the metal content of the intergalactic medium. By fine-tuning various model parameters and incorporating empirical constraints, we have tailored the model to match the statistical properties of Milky Way dwarf galaxies, such as their luminosity function and size–mass relation. We have validated our modified semi-analytic framework by undertaking a comparative analysis of the resulting galaxy–halo connection. We predict a total of $$300 ^{+75} _{-99}$$ satellites with an absolute V-band magnitude (MV) less than 0 within 300 kpc from our Milky Way analogues. The fraction of subhaloes that host a galaxy at least this bright drops to 50 per cent by a halo peak mass of ∼8.9 × 107 M⊙, consistent with the occupation fraction inferred from the latest observations of Milky Way satellite population.