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arXiv · 0902.0775

Feedback and the Formation of Dwarf Galaxy Stellar Halos

Greg Stinson·Julianne Dalcanton·Tom Quinn·Stephanie Gogarten·Tobias Kaufmann·James Wadsley
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Abstract

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 $v_{200}$ = 15 km s$^{-1}$ to 35 km s$^{-1}$, without the need for accretion of subhalos.

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Greg Stinson, Julianne Dalcanton, Tom Quinn, Stephanie Gogarten, Tobias Kaufmann, James Wadsley. 2009-02-04. Feedback and the Formation of Dwarf Galaxy Stellar Halos. https://doi.org/10.1111/j.1365-2966.2009.14555.x

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