The vast majority of galaxies, including the Milky Way, reside in loose collections called groups, which means that a thorough understanding of galaxy evolution cannot be achieved without considering the role of groups. X-ray and optical studies so far seem to show that the physical characteristics of groups deviate significantly from those of larger clusters. Groups dominated by spiral galaxies differ dramatically from groups dominated by ellipticals. This broad observational study of galaxy groups at low and intermediate redshift is designed to address two fundamental questions: what is the true distribution of mass in groups, and how have groups evolved over time? The principal (radio) observations will include an HI survey, a deep continuum survey, a study of bent radio sources, and a pilot experiment to map the diffuse continuum emission. Complementary optical observations will also be brought to bear on this study.
Broader impacts center on the Universe in the Park program of public outreach, involvement of undergraduate students in the research, and a continued commitment to attracting underrepresented minorities.
