AR 15052 (Archival Research)

Sun Jul 14 03:48:12 GMT 2024

Principal Investigator: Raymond Simons
PI Institution: University of Connecticut
Investigators (xml)

Title: Timing thick disk formation: an indirect census of stellar kinematics to z~2 from legacy Hubble imaging
Cycle: 25

Timing the assembly of kinematic structure in disk galaxies like the Milky Way is critically important for constraining models of galaxy evolution. We propose a novel study to indirectly measure the stellar velocity dispersion in disk galaxies back to z~2 using only Hubble imaging. We accomplish this by combining measurements of stellar scale heights from a sample of edge-on disks with stellar mass surface density maps from a sample of face-on disks. These samples are matched in redshift, mass and size. The typical stellar velocity dispersion is the direct product of these two measurements. This will provide the first census of stellar kinematics over such a large period in cosmic time, which will be used to place constraints on thick disk formation models. This proposal is uniquely suited for, and only made possible by, the high-resolution capabilities of Hubble and takes advantage of the wealth of archival HST/ACS-WFC3 data available through the legacy CANDELS survey. All of the data products and analysis software generated through this work will be released to the community.