Bar formation and evolution in the cosmological context: Inputs from the Auriga simulations

Understand

Galactic bars drive the internal evolution of spiral galaxies, while their formation is tightly coupled to the properties of their host galaxy and dark matter halo.

• To explore what drives bar formation in the cosmological context and how these structures evolve throughout cosmic history, we use the Auriga suite of magneto-hydrodynamical cosmological zoom-in simulations.
• We find that bars are robust and long-lived structures, and we recover a decreasing bar fraction with increasing redshift which plateaus around $\sim20\%$ at $z\sim3$.
• We find that bars which form at low and intermediate redshifts grow longer with time, while bars that form at high redshifts are born `saturated' in length, likely due to their merger-induced formation pathway.