A New Era for the Diffuse Universe
| Program ID | 19096 |
|---|---|
| Science Category | Galaxies |
| Program Type | Analysis |
| Category | Small |
| Principal Investigator | Jason Young |
| PI Institution | SETI Institute |
| Co-Investigators |
|
| Abstract | Our modern view of galaxy evolution connects a galaxy's ability to grow by forming new stars with its hydrogen gas supply. Yet, a class of diffuse, low-density galaxies called low surface brightness galaxies (LSBGs) present a paradox to challenge this view: LSBGs are gas rich, yet harbor relatively inefficient star formation. The nature of these objects makes them difficult to observe, especially in the near-IR, which provides an essential view of the mature stellar population. The Roman High-Latitude Wide-Area Survey (HLWAS) will revolutionize our understanding of the diffuse universe with high resolution coverage of thousands of known LSBGs at unprecedented depth, and with the detection of many more. This wide coverage + depth make Roman the only instrument able unlock this missing piece of galaxy evolution. We propose an in-depth analysis of 238 LSBGs with known redshifts, HI detections, and ancillary ground-based data within the HLWAS. This sample will allow us to a) determine the relative stability and long-term evolution of diffuse disks, and b) quantify the globular cluster luminosity function with respect to surface brightness and mass. These measurements, when combined with the HI data for this sample, will allow us to help determine the physical conditions that regulate galaxy evolution, i.e., to become an LSBG or a Milky Way analog. Additionally, by measuring the globular cluster turnover magnitude in gas-rich LSBGs, we will provide the community with a distance metric for LSBGs across the Roman surveys. |