9320250 Mouschovias The main objective of Dr. Mouschovias theoretical research project is a detailed, quantitative study of the role of ambipolar diffusion in the formation and contraction of protostellar cores in massive molecular clouds. The effect of interstellar dust particles in coupling the magnetic field to the dominant neutral species, and thereby affecting the contraction time and possibly the masses and sizes of protostellar cores, will be at the heart of the project. The goals of the project will be achieved through a systematic formulation and solution of a series of increasingly more complicated physical problems, beginning with simulations for which no changes in the numerical codes are needed and ending with simulations requiring substantial modification of the axisymmetric code to include a self-consistent calculation of the ionization equilibrium, including grain effects, at each time step of the evolution.