Interpreting Age Gradients in Dwarf Galaxies

Alyson M. Brooks, Roger Cohen, Ryan Leaman, Kristen B. W. McQuinn, F. Munshi

Publications: Other publicationOther

Abstract

Many dwarf galaxies appear to have "outside-in" age gradients, with the oldest stellar populations extending to the largest radii and younger stellar populations in the centers. In this proposal, we use the largest-ever simulated sample of dwarf galaxies to study the origin of age gradients in dwarfs across a range of mass, morphology, and environment. We demonstrate that the simulations reproduce observed age gradients in dwarf galaxies, and that they produce a diverse range of morphologies as a function of mass, as well as the observed trend in size-luminosity. We have identified a clear signature of age gradient variation as a function of star formation history. This signature is already being tested by archival HST resolved star observations. We will identify both the formation radius and final radius of every star particle, and disentangle re-shuffling of stars due to, e.g., mergers vs feedback mechanisms. A direct test of the theoretical age gradients against existing HST data has the potential to be a critical test of feedback, including the strength of the feedback model between different galaxy formation simulations. Thus, this theory work will both advance our understanding of the formation of observed dwarf galaxies, and a comparison against HST data will work to constrain galaxy formation models.
Original languageEnglish
TypeHST Proposal 17550
Publication statusPublished - Aug 2023

Austrian Fields of Science 2012

  • 103003 Astronomy
  • 103004 Astrophysics

Cite this