Time evolution of simulations G025 and G053, a low and intermediate stellar mass system (10^9.5 and 10¹⁰ M_⊙, respectively) in the central 2 kpc. Four running times are presented (from left to right, first six panels from top), with steps of 200 Myr, with a seed gas reservoir forming in G053 around t = 1400 Myr (between the two middle panels). Maps with a field of view of 2 kpc × 1 kpc of the total gas surface density, the mass of new stars (and old stars, as orange contours) and molecular gas density are shown as maps in the first to third rows for G025, and fourth to sixth rows for G053. In all maps, the bar is aligned with the x-axis. The two bottom rows show the radial profiles, averaged over the y-axis (±1 kpc), first with the gas profiles (total and molecular), and then the stellar density profiles (bottom row; old and new stars).