Simulating an Isolated Dwarf Galaxy with Multi-Channel Feedback and
  Chemical Yields from Individual Stars
  In order to better understand the relationship between feedback and galactic
chemical evolution, we have developed a new model for stellar feedback at grid
resolutions of only a few parsecs in global disk simulations, using the
adaptive mesh refinement hydrodynamics code Enzo. For the first time in galaxy
scale simulations, we simulate detailed stellar feedback from individual stars
including asymptotic giant branch winds, photoelectric heating, Lyman-Werner
radiation, ionizing radiation tracked through an adaptive ray-tracing radiative
transfer method, and core collapse and Type Ia supernovae. We furthermore
follow the star-by-star chemical yields using tracer fields for 15 metal
species: C, N, O, Na, Mg, Si, S, Ca, Mn, Fe, Ni, As, Sr, Y, and Ba. We include
the yields ejected in massive stellar winds, but greatly reduce the winds'
velocities due to computational constraints. We describe these methods in
detail in this work and present the first results from 500~Myr of evolution of
an isolated dwarf galaxy with properties similar to a Local Group, low-mass
dwarf galaxy. We demonstrate that our physics and feedback model is capable of
producing a dwarf galaxy whose evolution is consistent with observations in
both the Kennicutt-Schmidt relationship and extended Schmidt relationship.
Effective feedback drives outflows with a greater metallicity than the ISM,
leading to low metal retention fractions consistent with observations. Finally,
we demonstrate that these simulations yield valuable information on the
variation in mixing behavior of individual metal species within the multi-phase
interstellar medium.
