Neutral hydrogen in the region between the spiral arms of the Galaxy. Cloud structure

The clouds of neutral hydrogen found in the region between the Orion and Perseus spiral arms are investigated. The mass distribution of the clouds has a form of -Msup(-3/2). A continuation of this dependence of the lower masses gives the mean cloud mass and the mean gas density in intercloud medium and coefficient of filling in the volume of hydrogen clouds. The parameters of the clouds testify to the possible gas heating in the region between the spiral arms. It has been detected that more massive clouds have lower gas density. A graphical distribution of clouds according to their masses is given. After the comparative evaluation of theoretical calculations and the investigated data, a conclusion is made that the content of heavy elements in hydrogen clouds is normal and there is a possibility of gas density decrease in them as a result of collision of great masses of clouds