Feedback and the Formation of Dwarf Galaxy Stellar Halos
نویسنده
چکیده
Stellar population studies show that low mass galaxies in all environments exhibit stellar halos that are older and more spherically distributed than the main body of the galaxy. In some cases, there is a significant intermediate age component that extends beyond the young disk. We examine a suite of Smoothed Particle Hydrodynamic (SPH) simulations and find that elevated early star formation activity combined with supernova feedback can produce an extended stellar distribution that resembles these halos for model galaxies ranging from v200 = 15 km s −1 to 35 km s, without the need for accretion of subhalos.
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