Star formation in the central regions of disk galaxies

We simulate the formation of spiral-ring structures in the central gaseous disk in normal galaxies under the influence of a rotating bar potential. These spiral-ring regions, with high concentration of the mass of gas, are expected to be the sites of starburst rings. The location of the spiral-ring region depends on the size and rotation speed of the bar as well as the rotation law of the galaxy. Usually it is situated near the Lindblad resonances. We demonstrate that different Lindblad resonances generate different types of spiral-ring structure in galactic central regions. We further compare our results with the observations.