Kinematics and Dynamics of Dense Clouds

Abstract

Star formation is widely considered as resulting from the collapse of interstellar molecular clouds. The purpose of this paper is to review the observational evidences for collapse in dense clouds, and also for the factors which can play against collapse (turbulence, rotation, magnetic field). We shall also examine to which extent the maser sources (OH, H2O, SiO) can be related to star formation. An overlap with the review papers given by P. Thaddeus, P.G. Mezger, and to some extent by C.G. Wynn-Williams and L. Mestel appears unavoidable.