The Purest Dark Matter Halos and the Processes of Galaxy Evolution

University Of Arizona, Tucson AZ

Investigators

Abstract

A galaxy contains a mixture of gas, stars and dark matter. The gas and stars emit light, making them easy to study. But the dark matter is, well, dark: It does not emit light; so, it is difficult to study. Theories of galaxy formation try to account for the mixtures of gas, stars and dark matter in galaxies of all types. Recently, a new type of galaxy was discovered, the so-called ultra-diffuse galaxies (UDGs). These galaxies contain dark matter but, it seems, little else. This makes UDGs great places to test theories of galaxy formation. UDGs could also provide clues about the nature of dark matter. The race is on to find more UDGs, and the team has an ambitious plan to win the race. They will analyze ongoing surveys that cover huge swaths of the sky at optical wavelengths. The team will sift through the data to find UDGs. Then, they will study the properties of the UDGs. Senior team members will train junior team members. The team will partner with the Mount Lemmon Science Center in Arizona. There, the team will run a workshop for middle and high school teachers, plus host observatory visits by teachers and their students. The team's research will be featured in the workshop. The team will use deep, publicly-available imaging surveys to (1) produce a catalog of UDGs, (2) determine the global properties of UDGs over all environments, (3) contrast UDGs with normal galaxies, and (4) measure the profiles of the dark matter halos of UDGs.