Kennicutt–Schmidt law


In astronomy, the Kennicutt-Schmidt law is an empirical relation between the gas density and star formation rate in a given region. The relation was first examined by Maarten Schmidt in a 1959 paper where he proposed that the SFR surface density scales as some positive power of the local gas surface density. i.e.
In general, the SFR surface density is in units of solar masses per year per square parsec and the gas surface density in grams per square parsec. Using an analysis of gaseous helium and young stars in the solar neighborhood, the local density of white dwarfs and their luminosity function, and the local helium density, Schmidt suggested a value of . All of the data used were gathered from the Milky Way, and specifically the solar-neighborhood.
In 1989, Robert Kennicutt found that the H intensities of every galaxy in a sample of 7 could be fit with the Schmidt law. More recently, he examined the connection between gas density and SFR for nearly 100 nearby galaxies to estimate a value of.