Dr. Douglas Watson is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the University of Chicago. A longstanding problem in astrophysics is to understand how galaxies form. Such understanding is necessary to uncover how our Universe evolved and to gain insight into the origin of our own Milky Way Galaxy. One important aspect of understanding galaxy formation is to study how satellite galaxies relate to the dark matter subhalos in which they reside. Uncovering this connection provides a wealth of information about galaxy formation and hierarchical structure formation in the Universe. Satellite galaxies lead chaotic lives, yet an understanding of their spatial distribution gives clues into the relationship between the light and dark sides of the Universe.
In this project the fellow will focus on two principal aspects of galaxy formation theory that seek to shed light on the fate of satellite galaxies: First, there is a strong luminosity trend of the radial density profile of satellite galaxies such that bright satellites are poor tracers of the dominant, underlying dark matter. However, what is physically responsible for driving this result remains unclear. The fellow will seek to incorporate high resolution dark matter N-body simulations that will be able to resolve subhalos down to the very small scales of interest. Since satellite galaxies are believed to reside within subhalos, a detailed investigation of the spatial distribution of subhalos is crucial towards testing the concordance Lambda Cold Dark Matter model at the extreme small scales. Second, the fellow will investigate a new technique to use the spatial clustering of satellite galaxies to understand how their stellar mass loss occurs. Understanding how satellite galaxies can lose stellar mass can yield direct predictions for the amount of diffuse intrahalo light (IHL) at varying scales and may prove invaluable for providing insight into the physics of galaxy formation.
The broader impacts of this project include a significant educational component. One way to invigorate the general public and the next generation of great scientists is for astronomers to convey complex ideas with inspiration and clarity. The fellow will take a two-part approach to this endeavor: (1) improving public outreach efforts at the Adler Planetarium, and (2) training K-12 Chicago public school teachers in acquiring the skills to effectively teach science (astronomy in particular) to underserved, minority students. The first part involves the fellow developing new visualizations and engaging narratives for use in interactive presentations with museum visitors at the Adler Planetarium in Chicago. In the second part the fellow will help to construct and implement a new professional development workshop for teachers with a focus on astronomy. The experience with the Adler presentations will help inform the fellow on effective methods for taking astronomy into the classroom. The teaching workshop will not only allow teachers direct exposure to real scientists and the scientific method, but it will also assess the ability of astronomers to galvanize the underserved youth to pursue career paths in science. This activity will help enable teachers to inspire students to pursue careers in science.