Effects of Varying Mass Inflows on Star Formation in Nuclear Rings of Barred Galaxies

Observations indicate that the star formation rate (SFR) of nuclear rings varies considerably with time and is sometimes asymmetric rather than being uniform across a ring. To understand what controls temporal spatial distributions ring formation, we run semi-global, hydrodynamic simulations subject to time-varying and/or mass inflow rates. These controlled variations in lead while orbital period ($18\,{\rm Myr}$) radius ($600\,{\rm pc}$) remain approximately constant. We find both supernova feedback affect SFR. An oscillating $\Delta \tau_\text{in}$ amplitude 20 causes large-amplitude (a factor $\gtrsim 5$), quasi-periodic SFR, when \tau_\text{in} \gtrsim 50\,{\rm Myr}$. ISM weight midplane pressure track each other closely, establishing an instantaneous vertical equilibrium. The measured depletion consistent prediction from self-regulation theory provided delay between taken into account. responsible only for small-amplitude $\sim 2$) fluctuations SFR timescale $\lesssim 40\,{\rm Asymmetry does not necessarily rings. Only one dust lane suddenly increased by large factor, undergo transient lopsided formation.