9316241 Williams Research under this grant supports work associated with clusters of galaxies. Additional funds are being provided to carry out radio mapping of approximately 12 new compact groups of galaxies. This will double the sample of galaxies studied and make it possible to find compact groups of galaxies in different stages of merging into each other. At the present time the existing sample is too small to draw any definitive conclusions about how the neutral hydrogen in compact groups of galaxies evolves as the entire group coalesces into a single object. ***
