The Kennicutt–Schmidt Law and Gas Scale Height in Luminous and Ultraluminous Infrared Galaxies

A new analysis of high-resolution data from the Atacama Large Millimeter/submillimeter Array for five luminous or ultraluminous infrared galaxies gives a slope for the Kennicutt–Schmidt (KS) relation equal to for gas surface densities Σmol > 103 M⊙ pc−2 and an assumed constant CO-to-H2 conversion factor. The velocity dispersion of the CO line, σv, scales approximately as the inverse square root of Σmol, making the empirical gas scale height …