Archivi tag: surface photometry

The Formation and Evolution of Exponential Disks in Galaxies

Exponential stellar disks are ubiquitous. The stars in both spiral and dwarf galaxies are generally found to be organized in exponential disks, even to very low surface densities and in both stellar dominated and gas dominated galactic environments. But why is this? The associated gas disks do not fall off with radius in the same manner. Furthermore, star formation is highly lumpy. How does lumpy star formation produce distributions of stars that fall off smoothly. And how are these profiles maintained over many Gyr? Continua a leggere The Formation and Evolution of Exponential Disks in Galaxies